Objective: This study was conducted to examine the trends in patient visits to the emergency departments (EDs) during the coronavirus disease 2019 (COVID-19) pandemic and analyze the changes in the pattern of ED utilization over time. Methods: We analyzed the National Emergency Department Information System data on ED visits for 3 years, from January 1, 2018 to December 31, 2020. Results: A total of 25,260,790 patients visited the ED during the study period. There was a notable 23.3% decrease in visits in 2020 during the pandemic compared to the preceding year. The number of patients visiting the ED appeared to decrease in response to the increase in confirmed COVID-19 cases. In 2020, a total of 13,801 patients were diagnosed with COVID-19 in the ED, accounting for 22.7% of the confirmed COVID-19 cases in the country. In 2018, 2019, and 2020, ED visitors presenting with respiratory symptoms as their chief complaint numbered 1,438,137 (15.5%), 1,605,551 (17.7%), and 1,019,314 (14.7%), respectively. The length of stay of these patients increased at the regional and local emergency centers. However, a reverse trend was observed at local emergency medical agencies. Conclusion During the COVID-19 pandemic in 2020, patient visits to the ED decreased, irrespective of patient’s health status. The concentration of emergency and isolation-requiring patients at regional emergency medical centers and local emergency medical centers led to an increase in the length of stay. Further analysis and research are needed to assess the role of the local emergency medical agencies in the response to infectious diseases in the future.

Objective: This study was conducted to examine the trends in patient visits to the emergency departments (EDs) during the coronavirus disease 2019 (COVID-19) pandemic and analyze the changes in the pattern of ED utilization over time. Methods: We analyzed the National Emergency Department Information System data on ED visits for 3 years, from January 1, 2018 to December 31, 2020. Results: A total of 25,260,790 patients visited the ED during the study period. There was a notable 23.3% decrease in visits in 2020 during the pandemic compared to the preceding year. The number of patients visiting the ED appeared to decrease in response to the increase in confirmed COVID-19 cases. In 2020, a total of 13,801 patients were diagnosed with COVID-19 in the ED, accounting for 22.7% of the confirmed COVID-19 cases in the country. In 2018, 2019, and 2020, ED visitors presenting with respiratory symptoms as their chief complaint numbered 1,438,137 (15.5%), 1,605,551 (17.7%), and 1,019,314 (14.7%), respectively. The length of stay of these patients increased at the regional and local emergency centers. However, a reverse trend was observed at local emergency medical agencies. Conclusion During the COVID-19 pandemic in 2020, patient visits to the ED decreased, irrespective of patient’s health status. The concentration of emergency and isolation-requiring patients at regional emergency medical centers and local emergency medical centers led to an increase in the length of stay. Further analysis and research are needed to assess the role of the local emergency medical agencies in the response to infectious diseases in the future.

Objective: This study was conducted to examine the trends in patient visits to the emergency departments (EDs) during the coronavirus disease 2019 (COVID-19) pandemic and analyze the changes in the pattern of ED utilization over time. Methods: We analyzed the National Emergency Department Information System data on ED visits for 3 years, from January 1, 2018 to December 31, 2020. Results: A total of 25,260,790 patients visited the ED during the study period. There was a notable 23.3% decrease in visits in 2020 during the pandemic compared to the preceding year. The number of patients visiting the ED appeared to decrease in response to the increase in confirmed COVID-19 cases. In 2020, a total of 13,801 patients were diagnosed with COVID-19 in the ED, accounting for 22.7% of the confirmed COVID-19 cases in the country. In 2018, 2019, and 2020, ED visitors presenting with respiratory symptoms as their chief complaint numbered 1,438,137 (15.5%), 1,605,551 (17.7%), and 1,019,314 (14.7%), respectively. The length of stay of these patients increased at the regional and local emergency centers. However, a reverse trend was observed at local emergency medical agencies. Conclusion During the COVID-19 pandemic in 2020, patient visits to the ED decreased, irrespective of patient’s health status. The concentration of emergency and isolation-requiring patients at regional emergency medical centers and local emergency medical centers led to an increase in the length of stay. Further analysis and research are needed to assess the role of the local emergency medical agencies in the response to infectious diseases in the future.

Purpose: Since the introduction of robotic surgery, robots for colorectal cancer have replaced laparoscopic surgery, and a single-port robot (SPR) platform has been launched and is being used to treat patients. We analyzed the learning curve and initial complications of using an SPR platform in colorectal cancer surgery. Methods: We reviewed 39 patients who underwent SPR colectomy from April to October 2019. All surgeries were performed by the same surgeon using an SPR device. A learning curve was generated using the cumulative sum methodology to assess changes in total operation time, docking time, and surgeon console time. We grouped the patients into 3 groups according to the time period: the first 11 were phase 1, the next 11 were phase 2, and the last 17 were phase 3. Results: The mean age of the patients was 61.28±13.03 years, and they had a mean body mass index of 23.79±2.86 kg/m2. Among the patients, 23 (59.0%) were male, and 16 (41.0%) were female. The average operation time was 186.59±51.30 minutes, the average surgeon console time was 95.49±35.33 minutes, and the average docking time (time from skin incision to robot docking) was 14.87±10.38 minutes. The surgeon console time differed significantly among the different phases (P<0.001). Complications occurred in 8 patients: 2 ileus, 2 postoperation hemoglobin changes, 3 urinary retentions, and 1 complicated fluid collection. Conclusion In our experience, the learning curve for SPR colectomy was achieved after the 18th case.

Background: Female infertility is a crucial problem with significant implications for individuals and society. In this study, we explore risk factors for infertility in Korean women. Methods: A total of 986 female patients who visited six major infertility clinics in Korea were recruited from April to December 2014. Fertile age-matched controls were selected from two nationwide survey study participants. Conditional logistic regression after age-matching was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of each risk factor for infertility. Results: Women with a body mass index (BMI) < 18.5 kg/m2 had 1.35 times higher odds of infertility (OR, 1.35; 95% CI, 1.03–1.77), while those with a BMI ≥ 25.0 kg/m2 had even higher odds (OR, 2.06; 95% CI, 1.61–2.64) compared to women with a normal BMI (18.5 kg/m2 ≤ BMI < 25 kg/m 2 ). Ever-smokers exhibited 4.94 times higher odds of infertility compared to never-smokers (95% CI, 3.45–8.85). Concerning alcohol consumption, women who consumed ≥ 7 glasses at a time showed 3.13 times significantly higher odds of infertility than those who consumed ≤ 4 glasses at a time (95% CI, 1.79–5.48). Lastly, women with thyroid disease demonstrated 1.44 times higher odds of infertility compared to women without thyroid disease (95% CI, 1.00–2.08). Conclusion Female infertility in Korea was associated with underweight, obesity, smoking, alcohol consumption, and thyroid disease.

Background: Limited data are available on the mortality rates of patients receiving extracorporeal membrane oxygenation (ECMO) support for coronavirus disease 2019 (COVID-19). We aimed to analyze the relationship between COVID-19 and clinical outcomes for patients receiving ECMO. Methods: We retrospectively investigated patients with COVID-19 pneumonia requiring ECMO in 19 hospitals across Korea from January 1, 2020 to August 31, 2021. The primary outcome was the 90-day mortality after ECMO initiation. We performed multivariate analysis using a logistic regression model to estimate the odds ratio (OR) of 90-day mortality. Survival differences were analyzed using the Kaplan–Meier (KM) method. Results: Of 127 patients with COVID-19 pneumonia who received ECMO, 70 patients (55.1%) died within 90 days of ECMO initiation. The median age was 64 years, and 63% of patients were male. The incidence of ECMO was increased with age but was decreased after 70 years of age. However, the survival rate was decreased linearly with age. In multivariate analysis, age (OR, 1.048; 95% confidence interval [CI], 1.010–1.089; P = 0.014) and receipt of continuous renal replacement therapy (CRRT) (OR, 3.069; 95% CI, 1.312–7.180; P = 0.010) were significantly associated with an increased risk of 90-day mortality. KM curves showed significant differences in survival between groups according to age (65 years) (log-rank P = 0.021) and receipt of CRRT (log-rank P = 0.004). Conclusion Older age and receipt of CRRT were associated with higher mortality rates among patients with COVID-19 who received ECMO.

Background: A decline in masticatory function may indicate brain dysfunction related to dementia, but the relationship between masticatory function and dementia risk remains unclear. This study aimed to investigate whether masticatory function is associated with the risk of cognitive decline and dementia. Methods: Data were obtained from the nationwide prospective cohort study of randomly sampled community-dwelling Koreans aged ≥ 60 years. The 5,064 non-demented participants, whose number of chewing cycles per bite was assessed by clinical interview, were followed for 8 years with biennial assessments of cognitive performance and clinical diagnoses of all-cause dementia and Alzheimer’s disease (AD). Structural brain magnetic resonance imaging was collected from a subset of cohort participants and their spouses for imaging analyses. Results: Males who chewed ≥ 30 cycles/bite had faster decline in global cognition and memory function and were at higher risk for incident all-cause dementia (hazard ratio [HR], 2.91; 95% confidence interval [CI], 1.18–7.18) and AD (HR, 3.22; 95% CI, 1.14–9.11) compared to males with less than 10 cycles/bite. Additionally, increased chewing cycles in males were associated with reduced brain volume, particularly in regions involved in compensatory cognitive control of mastication. There was no significant association between chewing cycles and the risk of dementia or brain volume in females. Conclusion Older men who frequently chew their meals could be considered a notable population at risk for dementia who should be carefully assessed for their cognitive trajectories.

Background: We aimed to identify the prognostic factors for late intrahepatic recurrence (IHR), defined as recurrence more than two years after curative treatment of newly diagnosed hepatocellular carcinoma (HCC). Methods: This retrospective cohort study included patients with newly diagnosed, previously untreated, very early, or early HCC treated with initial curative treatment and followed up without recurrence for more than two years, excluding early IHR defined as recurrence within two years in single center. Late IHR-free survival (IHRFS) was defined as the time interval from initial curative treatment to the first IHR or death without IHR, whichever occurred first. Results: Among all the enrolled 2,304 patients, 1,427 (61.9%) underwent curative intent hepatectomy and the remaining 877 (38.1%) underwent local ablative therapy (LAT). During the follow-up after curative treatment (median, 82.6 months; range, 24.1 to 195.7), late IHR was detected in 816 (35.4%) patients. In the multivariable analysis, age, male sex, cirrhotic liver at diagnosis, type of initial treatment, and modified albumin-bilirubin (mALBI) grade were significant prognostic baseline factors. Furthermore, mALBI grade at three (2a vs. 1, P = 0.02, hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.04–1.70; 2b/3 vs. 1, P = 0.03; HR, 1.42; 95% CI, 1.03–1.94) and six months (2b/3 vs. 1; P = 0.006; HR, 1.61; 95% CI, 1.13–2.30) after initial curative treatment was also a significant prognostic factor for late IHR. Conclusion After curative treatment for newly diagnosed early HCC, the mALBI grade at three and six months after initial curative treatment, as well as at baseline, was one of the most crucial prognostic factors for late IHR.

Purpose: The advances in the treatment of retinoblastoma have enabled salvaging the globe in advanced stages with intra-arterial chemotherapy (IAC). We developed a strategy of alternate application of systemic intravenous chemotherapy (IVC) and IAC (referred to as alternate systemic IVC and IAC; ASIAC) to reduce central nervous metastases during IAC and examined its efficacy and safety in eye globe salvage in this study. Materials and Methods: Between January 2010 and February 2021, 43 eyes of 40 patients received ASIAC treatment for retinoblastoma at the Yonsei Cancer Center, Yonsei University Health System. Their medical records were reviewed retrospectively to evaluate the eye salvage rate (ESR), defined from diagnosis to enucleation. High-risk retinoblastoma was defined as group D or E by the International Classification of Retinoblastoma. Results: The study enrolled 38 and five cases of high-risk and low-risk retinoblastoma, respectively. In total, 178 IAC and 410 IVC courses were administered, with a median of 4 (interquartile range [IQR], 3.0 to 5.0) IAC and 9 (IQR, 6.0 to 11) IVC courses per eye, respectively. The 5-year ESR was 60.4%±8.7% for the whole cohort, 100% for low-risk retinoblastoma, and 53.6%±9.8% for high-risk retinoblastoma. Among those diagnosed since 2015, the 5-year ESR for high-risk retinoblastoma was 63.5%±14.0%. Fifteen eyes underwent enucleation; no viable tumor was found in three enucleated eyes. There were no deaths in this cohort. Conclusion Primary IAC-IVC (i.e., ASIAC) for patients with retinoblastoma was tolerable and effective in salvaging the eye and maintaining survival.

Background: This study investigated the results of component asymmetry (CA) in bilateral cementless total hip arthroplasty (THA). Methods: This study included 300 patients, who underwent bilateral cementless THA between April 2000 and December 2017. They were divided into the component symmetry (CS) and CA groups; CA group was sub-classified into acetabular component asymmetry (ACA) and femoral component asymmetry (FCA). Radiologic and clinical outcomes of the CA group were compared with those of the CS group. Results: The incidence of CA was 25.7% (77/300 patients), including 55 patients with ACA, 34 patients with FCA, and 12 with both components asymmetric. The mean time interval between operations in the CA group was significantly longer than that in the CS group (p < 0.001). The mean differences in horizontal and vertical distances from teardrop to the center of rotation of the acetabular component between both hips in the ACA group were significantly larger than those in the CS group (p = 0.033 and p < 0.001, respectively). The mean femoral component alignment angle difference between both hips was significantly larger in the FCA group than in the CS group (p < 0.001). The mean Harris Hip Score at last follow-up of the CA group was similar to that of the CS group. Conclusions CA in patients undergoing bilateral cementless THA was not rare, especially with a longer time interval between operations. Regardless of CA, when stable fixation of the components was achieved, satisfactory radiologic and clinical outcomes were obtained.