Background: Barriers to treatment with intravenous thrombolysis (IVT) for patients with acute ischemic stroke (AIS) in South Korea remain incompletely characterized. We analyze a nationwide prospective cohort to determine patient-level features associated with delayed presentation and non-treatment of potential IVT-eligible patients. Methods: We identified consecutive patients with AIS from 01/2011 to 08/2023 from a multicenter and prospective acute stroke registry in Korea. Patients were defined as IVT candidates if they presented within 4.5 hours from the last known well, had no lab evidence of coagulopathy, and had National Institute of Health Stroke Scale (NIHSS) ≥ 4. Multivariable generalized linear mixed regression models were used to investigate the associations between their characteristics and the IVT candidates or the use of IVT among the candidates. Results: Among 84,103 AIS patients, 41.0% were female, with a mean age of 69 ± 13 years and presentation NIHSS of 4 [interquartile range, 1–8]. Out of these patients, 13,757 (16.4%) were eligible for IVT, of whom 8,179 (59.5%) received IVT. Female sex (adjusted risk ratio [RR], 0.90; 95% confidence interval [CI], 0.86–0.94) and lower years of education (adjusted RR, 0.90; 95% CI, 0.84–0.97 for 0–3 years, compared to ≥ 13 years) were associated with a decreased likelihood of presenting as eligible for IVT after AIS; meanwhile, young age (adjusted RR, 1.12; 95% CI, 1.01–1.24 for ≤ 44 years, compared to 75–84 years) was associated with an increased likelihood of being an IVT candidate. Among those who were eligible for IVT, only age was significantly associated with the use of IVT (adjusted RR, 1.09; 95% CI, 1.03–1.16 for age 65–74 and adjusted RR, 0.83; 95% CI, 0.76–0.90 for ≥ 85 years, respectively). Conclusion Most patients with AIS present outside IVT eligibility in South Korea, and only 60% of eligible patients were ultimately treated. We identified increased age, female sex and lower education as key features on which to focus interventions for improving IVT utilization.

Background: Primary Merkel cell carcinoma of the salivary gland is currently not listed in the World Health Organization classification. However, cases of Merkel cell type neuroendocrine carcinomas of the salivary gland with perinuclear cytokeratin 20 positivity have been intermittently reported. We here investigated the clinicopathologic features of additional cases. Methods: Data of four cases of Merkel cell type small cell neuroendocrine carcinoma of the salivary gland were retrieved. To confirm the tumors’ primary nature, clinical records and pathologic materials were reviewed. Optimal immunohistochemical staining was performed to support the diagnosis. Results: All tumors were located in the parotid gland. Possibilities of metastasis were excluded in all cases through a meticulous clinicopathological review. Tumor histology was consistent with the diagnosis of small cell neuroendocrine carcinoma. Tumors’ immunohistochemical phenotypes were consistent with Merkel cell carcinoma, including Merkel cell polyomavirus large T antigen positivity in two of the four cases. Conclusions Merkel cell carcinomas can originate in salivary glands and are partly associated with Merkel cell polyomavirus infection as in cutaneous Merkel cell carcinomas.

Background: and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes. Methods: We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data. Results: Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2 , and a 3-month modified Rankin Scale score of ≥4. Conclusion Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.

Cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) is a neurodegenerative disorder caused by a biallelic expansion of pentanucleotide repeats in the RFC1 gene. Previous studies have reported up to 22% of patients with late-onset ataxia harbor this pathogenic repeat expansion. Despite its relatively high prevalence, CANVAS is often underdiagnosed because the disease is not well recognized and genetic testing is not performed in clinical practice. Here, we present a patient with characteristic clinical features, confirmed by genetic testing.

Background: This study aimed to assess the severity of postoperative delirium (PD) in elderly patients who underwent reverse total shoulder arthroplasty (rTSA) for irreparable massive rotator cuff tears (mRCTs) under general anesthesia (GA) compared to those under interscalene block (IB). Methods: Forty elderly patients aged 65 years or older diagnosed with an irreparable mRCT who underwent rTSA were included in the prospective case-controlled study. Of these, 20 patients were operated under GA and the other 20 under IB. The average age was 77.1 years (range, 65–95 years). The severity of delirious symptoms was evaluated by the Delirium Rating Scale–revised–98 (DRS) score from the patients or guardians before the surgery and at 0, 3, and 7 days and 1, 3, and 6 months after the surgery and compared between the 2 groups. Results: Immediately after surgery, the visual analog scale score difference between the groups was statistically significant, with the GA group at 6.25 (standard deviation, ± 0.85) and the IB group at 3.80 (± 0.62) (p < 0.001). On the day of operation, the mean DRS score in the GA and IB groups were 9.10 (± 5.63) and 6.60 (± 5.33), respectively (p = 0.157). On day 3 of surgery, the mean DRS score in the GA group peaked to 9.95 (± 8.73), while in the IB group, it declined to 6.40 (±5.81) (p = 0.138). After 3 days, DRS scores showed a decreasing trend in both groups. When comparing the mean change (∆) from the preoperative baseline scores to the postoperative values, the ∆DRS score was significantly higher with 4.15 (± 4.53) points in the GA group as compared to 1.30 (± 1.92) in the IB group (p = 0.014). Conclusions IB can be an attractive and efficient anesthetic choice in preventing PD for elderly patients undergoing rTSA for irreparable mRCTs. The IB group showed lower DRS scores and a peak on day 0 compared to the higher DRS scores and peak on day 3 in the GA group. Additionally, IB showed less pain than GA.

Background: Anterior dislocation in epilepsy patients is relatively severe, difficult to treat, and prone to recurrence. The purpose of this study was to compare the results of arthroscopic Bankart repair and the open Latarjet procedure in epilepsy patients who had anterior shoulder instability and to compare the results of the open Latarjet procedure in epilepsy and non-epileptic groups. Methods: A total of 57 shoulders (34 dominant) in 55 patients (18–50 years, 45 men and 10 women) with anterior glenohumeral instability were included in the study and the average follow-up was 24 months. Out of 21 epilepsy patients (23 shoulders), 11 were treated with the open Latarjet procedure and 12 with arthroscopic Bankart repair. Additionally, comparisons were made between the 34 non-epileptic patients who underwent the open Latarjet procedure and the epilepsy patients who underwent the same procedure. Results: In the epilepsy group, all 12 patients who underwent Bankart repair had on-track lesions, and all 11 patients who underwent the Latarjet procedure had off-track lesions. In the non-epilepsy group, all cases were off-track lesions. In the epilepsy group, there was no significant difference in the postoperative clinical outcome and recurrence rate between the Bankart repair and Latarjet procedure groups. In the Latarjet group, postoperative re-dislocation rate in the non-epilepsy patients was 14% (5/34 cases), compared to 45% (5/11 cases) in the epilepsy patients, 4 of which 4 occurred during seizures. It was 41% in the Bankart repair group for on-track lesions, which was similar to the recurrence rate after the Latarjet for off-track lesions in the epilepsy group. Conclusions After the Latarjet procedure, the functional outcomes in the epilepsy group were similar to those in the non-epilepsy group, except for the higher re-dislocation rate. With either of the surgical procedures, the re-dislocation rate secondary to seizures was very high. Despite the presence of on-track lesions, the Latarjet procedure would be more preferrable for anterior stabilization in epilepsy patients, in view of the high recurrence rate with arthroscopic Bankart repair.

Background: and Purpose: Amyloid-beta (Aβ) plaques are key in Alzheimer’s disease (AD), with Aβ positron emission tomography imaging enabling non-invasive quantification.To address regional Aβ deposition, we developed regional Centiloid scales (rdcCL) and commercialized them through the computed tomography (CT)-based BeauBrain Amylo platform, eliminating the need for three-dimensional T1 magnetic resonance imaging (MRI). Objective: We aimed to establish robust regional Aβ cutoffs using the commercialized BeauBrain Amylo platform and to explore the prevalence of subgroups defined by global, regional, and striatal Aβ cutoffs across cognitive stages. Methods: We included 2,428 individuals recruited from the Korea-Registries to Overcome Dementia and Accelerate Dementia Research project. We calculated regional Aβ cutoffs using Gaussian Mixture Modeling. Participants were classified into subgroups based on global, regional, and striatal Aβ positivity across cognitive stages (cognitively unimpaired [CU], mild cognitive impairment, and dementia of the Alzheimer’s type). Results: MRI-based and CT-based global Aβ cutoffs were highly comparable and consistent with previously reported Centiloid values. Regional cutoffs revealed both similarities and differences between MRI- and CT-based methods, reflecting modality-specific segmentation processes. Subgroups such as global(−)regional(+) were more frequent in non-dementia stages, while global(+)striatal(−) was primarily observed in CU individuals. Conclusions Our study established robust regional Aβ cutoffs using a CT-based rdcCL method and demonstrated its clinical utility in classifying amyloid subgroups across cognitive stages. These findings highlight the importance of regional Aβ quantification in understanding amyloid pathology and its implications for biomarker-guided diagnosis and treatment in AD.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background/Aims: We previously reported that patients with moderate-to-severe ulcerative colitis (UC) often experience common mental disorders (CMDs) such as anxiety and depression, necessitating immediate psychological interventions within the first 4 weeks of diagnosis. In this 3-year follow-up study of the MOSAIK cohort in Korea, we examined the effects of CMDs at initial diagnosis on clinical outcomes and health-related quality of life (HRQoL). Methods: We examined differences in clinical outcomes (evaluated based on clinical response, relapse, hospitalization, and medication use) and HRQoL (assessed using the Inflammatory Bowel Disease Questionnaire [IBDQ] and Short Form 12 [SF-12]) according to Hospital Anxiety and Depression Scale (HADS) scores at diagnosis. Results: In a study involving 199 UC patients, 47.7% exhibited significant psychological distress (anxiety and/or depression) at diagnosis. Clinical follow-up showed no major differences in outcomes, including remission rates, response rates, or hospitalization rates, between patients with anxiety or depression at diagnosis and patients without anxiety or depression at diagnosis. The HRQoL at the end of follow-up was notably lower in those with baseline CMDs, particularly anxiety, across all domains of the IBDQ and SF-12. Linear mixed-effect models revealed that higher HADS scores, as well as higher Mayo scores, were independently associated with lower IBDQ scores and both summary domains of the SF-12. Additionally, regular attendance at follow-up visits during the study period was also related to improvements in HRQoL (all p<0.05). Conclusions While CMDs present at the time of UC diagnosis did not influence long-term clinical outcomes, they persistently impaired HRQoL. Our findings support the routine incorporation of psychological interventions into the long-term management of moderate-to-severe UC.