Yonsei University Health System Research Articles

Expansion of thyroid surgical territory through 10,000 cases under the da Vinci robotic knife

With the progress of robotic transaxillary thyroid surgery (RTTS), the indications for this procedure have gradually expanded. This study presents the insights gained from performing 10,000 RTTS cases at a single institution, along with the expansion of indications over time. RTTS was performed on 10,000 patients using the da Vinci robot system between October 2007 and April 2023 at the Yonsei University Health System, Seoul, Korea. Among 10,000 patients, 9461 (94.0%) were diagnosed with thyroid cancer, whereas 539 (5.4%) had either a benign thyroid nodule or Graves’ disease. Surgical procedures were performed using four-arm-based robots (da Vinci S, Si, or Xi) for 8408 cases (84.1%), with the remaining 1592 cases (15.9%) being performed using the da Vinci SP surgical robotic system. Notably, for 53 patients with nodules ≥ 5 cm, which were not included in the eligibility criteria of the previous study, RTTS was performed safely without significant complications. The most common postoperative complication was transient hypoparathyroidism (37.91%), and recurrence occurred in 100 patients with thyroid cancer (1.1%). In conclusion, RTTS appears safe and feasible from both surgical and oncological perspectives, and the spectrum of indications suitable for RTTS surgery is progressively expanding.

External Validation of Deep Learning-Based Cardiac Arrest Risk Management System for Predicting In-Hospital Cardiac Arrest in Patients Admitted to General Wards Based on Rapid Response System Operating and Nonoperating Periods: A Single-Center Study.

The limitations of current early warning scores have prompted the development of deep learning-based systems, such as deep learning-based cardiac arrest risk management systems (DeepCARS). Unfortunately, in South Korea, only two institutions operate 24-hour Rapid Response System (RRS), whereas most hospitals have part-time or no RRS coverage at all. This study validated the predictive performance of DeepCARS during RRS operation and nonoperation periods and explored its potential beyond RRS operating hours. Retrospective cohort study. In this 1-year retrospective study conducted at Yonsei University Health System Severance Hospital in South Korea, DeepCARS was compared with conventional early warning systems for predicting in-hospital cardiac arrest (IHCA). The study focused on adult patients admitted to the general ward, with the primary outcome being IHCA-prediction performance within 24 hours of the alarm. We analyzed the data records of adult patients admitted to a general ward from September 1, 2019, to August 31, 2020. None. Performance evaluation was conducted separately for the operational and nonoperational periods of the RRS, using the area under the receiver operating characteristic curve (AUROC) as the metric. DeepCARS demonstrated a superior AUROC as compared with the Modified Early Warning Score (MEWS) and the National Early Warning Score (NEWS), both during RRS operating and nonoperating hours. Although the MEWS and NEWS exhibited varying performance across the two periods, DeepCARS showed consistent performance. The accuracy and efficiency for predicting IHCA of DeepCARS were superior to that of conventional methods, regardless of whether the RRS was in operation. These findings emphasize that DeepCARS is an effective screening tool suitable for hospitals with full-time RRS, part-time RRS, and even those without any RRS.

Laparoscopic-Assisted Colonic Resection for Splenic-Flexure Cancer With D3 Lymphadenectomy.

1 Coloproctology Unit, General Surgery III, Surgical Department, Hospital Dr. Domingo Luciani, Venezuela 2 Department of Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea Funding/Support: None reported. Financial Disclosures: None reported. Informed consent of the patient was given. Correspondence: Seung Yoon Yang, M.D., Department of Surgery, Yonsei University College of Medicine, Seoul, South Korea, 50-1 Yonsei-ro Seodaemun-gu Yonsei University Health System, 03722. Seoul, South Korea. Email: [email protected]

Single-Port Transaxillary Robotic Modified Radical Neck Dissection (STAR-RND): Initial Experiences.

This study aimed to demonstrate the usefulness of single-port transaxillary robotic modified radical neck dissection (STAR-RND) for metastatic thyroid cancer, and its potential to make small and invisible surgical wounds possible compared to open modified radical neck dissection. Between January 2020 and July 2021, 30 thyroid cancer patients who underwent lateral neck dissection surgery with the da Vinci SP at Yonsei University Health System (Seoul, Korea) were studied. All 30 patients, diagnosed with papillary thyroid cancer were women. The average operating time was 293.80 ± 36.58 (min), and the average postoperative hospital stay was 4.77 ± 0.57 (days). All patients were discharged after the expected number of hospitalization days without major complications. STAR-RND is technically feasible and safe with a short length of the incision. To our knowledge, this is the first report on the use of a single-port robotic system for modified radical neck dissection. LEVEL OF EVIDENCE BY USING 2011 OCEBM: 4 Laryngoscope, 133:709-714, 2023.

The Efficacy of Alternate Systemic Intravenous Chemotherapy and Intra-arterial Chemotherapy Approach for Eye Globe Salvage in Retinoblastoma.

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. 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. 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. Primary IAC-IVC (i.e., ASIAC) for patients with retinoblastoma was tolerable and effective in salvaging the eye and maintaining survival.

Effect of Steroid Replacement on Long-Term Kidney Function in Patients With Adrenal Insufficiency

ObjectiveThe prevalence of adrenal insufficiency (AI) is increasing with an increase in the elderly population. Steroid replacement therapy (SRT) is often required in patients with AI because of acute symptoms and complications. The long-term effects of SRT on kidney function have not been well elucidated. MethodsOverall, 788 patients diagnosed with AI between 2010 and 2015 at Yonsei University Health System were retrospectively evaluated. SRT was defined when an equivalent dose of ≥5 mg/d of hydrocortisone was initiated within 30 days of AI diagnosis and maintained for >30 days. Those not included in the SRT group were identified as the no-SRT group. The primary outcome was 40% reduction in the estimated glomerular filtration rate compared with baseline sustained for ≥30 days or end-stage kidney disease development. ResultsThe mean age of was 63.1 ± 15.4 years, and 43.0% were men. The SRT group comprised 387 patients. During a median follow-up duration of 4.1 years, the primary outcome occurred in 118 (15.0%) patients. The outcome incidence rate was higher in the SRT group (4.61/100 patient-years) than in the no-SRT group (2.76/100 patient-years). When the subdistribution hazard ratio for kidney outcome was assessed with death as a competing risk, the risk was 67% higher in the SRT group than in the no-SRT group (subdistribution hazard ratio, 1.67; 95% confidence interval, 1.16-2.45; P = .006). This association was maintained with inverse probability of treatment weighting and adjustment for confounding variables. ConclusionKidney function decline was more prominent in patients with AI who received SRT. Further prospective evaluations are needed to confirm these findings.

Safety and Performance of Harmonic® HD 1000i Shears in Thoracoscopic Procedures: A Retrospective Study

Background: Ultrasonic energy devices are utilized for transection, incision, and hemostasis in traditional open and laparoscopic procedures. The Harmonic HD 1000i Shears, designed to deliver a precise amount of thermal energy during tissue transection and vessel sealing, has been utilized in many specialties. This study aimed to confirm real-world safety and performance of the Harmonic device in two thoracoscopic procedures: lobectomy and segmentectomy. Methods: The primary endpoint of this retrospective, observational, single-arm study was rate of post-operative blood transfusions related to study device or procedure. Secondary endpoints included occurrence of intra- and post-operative adverse events (AEs) or complications device- or procedure-related, and rate of required additional hemostatic measures. Adults included those who underwent thoracoscopic lobectomy or segmentectomy where HD 1000i shears were used while excluding those where additional advanced energy devices were used. The study was conducted at Severance Hospital, Yonsei University Health System, South Korea from May 1, 2018, to November 30, 2020. Results: Subjects included n = 766 lobectomies (mean age 63.79, 52% male) and n = 215 segmentectomies (mean age 63.19, 54% male). Estimated blood loss was 50 mL (0 min, 3200 max) and 20 mL (0 min, 800 max), intraoperative transfusion rate 0.001% and 0%, intraoperative complication/AE rate 1% and 2%, and post-operative complication/AE rate 9% and 4% in the lobectomy and segmentectomy groups, respectively. Median operative times were 108 min. (35 min, 395 max) for lobectomies and 105 min. (32 min, 574 max) for segmentectomies. Conclusion: Given the low rate of blood loss and intra- and post-operative complication/AE rates, HD 1000i can be used confidently for thoracoscopic pulmonary resection in adults.

Single-port transaxillary robotic thyroidectomy (START): 200-cases with two-step retraction method

BackgroundThis study aims to report the results of a pioneering clinical study using the single-port transaxillary robotic thyroidectomy (START) for 200 patients with thyroid tumor and to introduce our novel two-step retraction method.MethodsSTART was performed on consecutive 200 patients using the da Vinci Single-Port (SP) robot system from January 2019 to September 2020 at the Yonsei University Health System, Seoul, Korea. The novel two-step retraction technique, in which a 3.5 cm long incision is made along the natural skin crease, was used for the latter 164 patients. The surgical outcome and invasiveness of the SP two-step retraction method were analyzed.ResultsAmong the 200 cases who underwent START, 198 were female and 2 were male, with a mean age of 34.7 (range: 13–58 years). Thyroid lobectomy was performed for 177 patients and total thyroidectomy was performed for 23 patients. Ten patients had benign thyroid nodules, whereas the other 190 had thyroid malignancy. The mean body mass index (BMI) was 22.2 ± 3.7 kg/m2 (range: 15.9–37.0 kg/m2). All of the operations were performed successfully without any open conversions, and patients were discharged on postoperative day 3 or 4 without significant complication. The mean operative time for thyroid lobectomy with the two-step retraction method was 116.69 ± 23.23 min, which was similar to that in the conventional robotic skin flap method (115.33 ± 17.29 min). We could minimize the extent of the robotic skin flap dissection with the two-step retraction method.ConclusionsSTART is a practical surgical method. By employing the new two-step retraction method, we can maximize the cosmetic and functional benefits for patients and reduce the workload fatigue of surgeons by increasing robotic dependency.

Acral melanoma detection using dermoscopic images and convolutional neural networks

Acral melanoma (AM) is a rare and lethal type of skin cancer. It can be diagnosed by expert dermatologists, using dermoscopic imaging. It is challenging for dermatologists to diagnose melanoma because of the very minor differences between melanoma and non-melanoma cancers. Most of the research on skin cancer diagnosis is related to the binary classification of lesions into melanoma and non-melanoma. However, to date, limited research has been conducted on the classification of melanoma subtypes. The current study investigated the effectiveness of dermoscopy and deep learning in classifying melanoma subtypes, such as, AM. In this study, we present a novel deep learning model, developed to classify skin cancer. We utilized a dermoscopic image dataset from the Yonsei University Health System South Korea for the classification of skin lesions. Various image processing and data augmentation techniques have been applied to develop a robust automated system for AM detection. Our custom-built model is a seven-layered deep convolutional network that was trained from scratch. Additionally, transfer learning was utilized to compare the performance of our model, where AlexNet and ResNet-18 were modified, fine-tuned, and trained on the same dataset. We achieved improved results from our proposed model with an accuracy of more than 90 % for AM and benign nevus, respectively. Additionally, using the transfer learning approach, we achieved an average accuracy of nearly 97 %, which is comparable to that of state-of-the-art methods. From our analysis and results, we found that our model performed well and was able to effectively classify skin cancer. Our results show that the proposed system can be used by dermatologists in the clinical decision-making process for the early diagnosis of AM.

Paired comparisons of mutational profiles before and after brachytherapy in asian uveal melanoma patients

Uveal melanoma(UM) is the most common primary intraocular malignancy in adults. However, the incidence of UM in Asia is 10 to 20 times less than in Western populations. Therefore, for the first time, we report our whole exome sequencing (WES) data analysis to discover differences in the molecular features of Asian and Western UM, and to determine the disparities between the primary tumor before brachytherapy and enucleated samples after brachytherapy. WES of 19 samples (13 primary tumors, 5 enucleation samples after brachytherapy, and 1 liver metastasis) from 13 patients diagnosed with UM and treated between 2007 and 2019 at the Yonsei University Health System (YUHS) were analyzed using bioinformatics pipelines. We identified significantly altered genes in Asian UM and changes in mutational profiles before and after brachytherapy using various algorithms. GNAQ, BAP1, GNA11, SF3B1 and CYSLTR2 were significantly mutated in Asian UM, which is similar that reported frequently in previous Western-based UM studies. There were also similar copy number alterations (M3, 1p loss, 6p gain, 8q gain) in both groups. In paired comparisons of the same patients, DICER1 and LRP1B were distinctly mutated only in tumor samples obtained after brachytherapy using rare-variant association tests (P = 0.01, 0.01, respectively). The mutational profiles of Asian UM were generally similar to the data from previous Western-based studies. DICER1 and LRP1B were newly mutated genes with statistical significance in the regrowth samples after brachytherapy compared to the primary tumors, which may be related to resistance to brachytherapy.

Historical overview of the Department of Neurosurgery at Yonsei University College of Medicine in the Republic of Korea.

Originally founded in 1885, Gwanghyewon later became the Severance Hospital (named after philanthropist Louis Severance, who supported and funded the construction of a modern hospital) and Yonsei University College of Medicine. The Department of Neurosurgery at Severance Hospital was established in 1957, and its residency program began in 1961. Currently, the Department of Neurosurgery has 34 professors and 17 fellows; specialties include vascular, functional, pediatric, tumor, skull base, and spine neurosurgery. With its state-of-the-art neurosurgical facilities and services, the Department of Neurosurgery has developed into a department of excellence within the Yonsei University Health System. In this vignette, the authors present a historic overview of the Department of Neurosurgery.

Minimally invasive (laparoscopic and robot-assisted) versus open approach for central pancreatectomies: a single-center experience.

There continues to be an interest in minimally invasive approaches to pancreatic surgery. At our institution, there has been a progressive change from an open to minimally invasive surgery (MIS) (laparoscopic, robotic, or laparoscopic-robotic) approach for central pancreatectomies (CP). The aim of this study was to evaluate surgical outcomes with open CP (O-CP) versus minimally invasive CP (MI-CP). A retrospective medical review of patients who underwent CP between 1993 and 2018 at Yonsei University Health System, Seoul, Korea was performed. Short-term perioperative outcomes were compared between O-CP and MI-CP. Thirty-one CPs (11 open, 20 MIS) were identified during the study period. No difference was observed in admission days between O-CP and MI-CP (21.2 vs. 16.7days, p = 0.340), although operating time was significantly increased in the MI-CP group (296.8 vs. 374.8min, p = 0.036). Blood loss was significantly less in MI-CP vs. O-CP (807.1 vs. 214.0 mls, p = 0.001), with no difference in post-operative new-onset diabetes (9% vs. 5%). The overall post-operative pancreatic fistula rate was 25.8%, and no significant difference between O-CP and MI-CP or complication rates (45% vs. 40%) was observed. Despite increased operative time, MI-CP is feasible and comparable to conventional O-CP with regard to surgical outcomes in well-selected patients.

Reversibility of Endoscopic Features after Treatment for Eosinophilic Esophagitis.

PurposeThe prevalence and incidence of eosinophilic esophagitis (EoE) are increasing worldwide. Despite increased understanding of inflammatory pathogenesis, changes in endoscopic features after treatment of EoE have not been clearly described. We aimed to investigate the reversibility of endoscopic features of EoE after treatment.Materials and MethodsOut of 58 adult subjects who were diagnosed with EoE at the Yonsei University Health System from July 2006 to August 2019, we recruited 33 subjects (30 males; mean age: 42 years) whose pre-treatment and post-treatment endoscopic images were available. Endoscopic features included both inflammatory and fibrostenotic features. Exudate, edema, furrow, and crepe paper-like mucosa were classified as inflammatory features. Ring and stricture were classified as fibrostenotic features. We compared changes in endoscopic features after treatment for EoE.ResultsAfter treatment, clinical symptoms improved in all patients. The following endoscopic features were observed before treatment: furrow (81.8%), edema (90.9%), exudate (42.4%), ring (27.3%), crepe paper-like mucosa (15.2%), and stricture (3.0%). Endoscopic remission was achieved in 21 patients (63.6%). Inflammatory features were reversible (72.7%, p<0.001), whereas fibrostenotic features were not (10%, p=0.160). Exudate had resolved in 92.9% of patients, edema in 70% and furrow in 88.9%. Ring and stricture persisted in almost all of the patients (9/10) who had these endoscopic features before treatment.ConclusionWe outlined the reversibility of endoscopic inflammatory features of EoE. Fibrostenotic features were irreversible after esophageal remodeling in patients with EoE. However, further validation studies with long-term follow-up are needed.

P0618PREOPERATIVE LOW URINE SPECIFIC GRAVITY PREDICTS ACUTE KIDNEY INJURY AFTER CARDIAC SURGERY

Abstract Background and Aims Acute kidney injury (AKI) is a common and serious complication following cardiac surgery. However, strategies that effectively predict AKI risk before cardiac surgery are scarce. Recent investigations identified urinary osmolality to be associated with non-glomerular kidney damage in normal kidney function individuals, suggesting urine concentration ability to be a surrogate of early kidney damage. Therefore, hypothesizing that urine specific gravity (SG) could reflect asymptomatic kidney damage, the clinical implication of preoperative urine specific gravity on AKI occurrence after cardiac surgery was investigated in subjects with normal kidney function. Method A total of 4135 patients who underwent coronary artery bypass or valve surgery at Yonsei University Health System from were enrolled. Patients whose eGFR was lower than 60mL/min/1.73m2 were excluded. Fasting urinary SG was measured from the morning first void a day before the surgery. The patients were divided into tertiles based on urine SG. The primary outcome was occurrence of AKI within 48hours of cardiac surgery. AKI was defined according to Acute Kidney Injury Network criteria. Results The mean age of the patients was 60 years and 60% were male. Diabetes consisted of 25.6% of the patients and 54.5% were hypertensive. The mean eGFR and urine SG was 98.8mL/min/1.73m2 and 1.020, respectively. AKI developed in 1,089 (26.3%) patients. The incidence of AKI was highest in the lowest urine SG tertile group (410, 29.0%) and lowest in the highest tertile group (304, 23.5%) (P &amp;lt; 0.001). Multivariable logistic regression analysis revealed that being included in the lowest preoperative urine SG tertile group was significantly related with higher post cardiac surgery AKI incidence risk (odd ratio (OR), 1.33; CI, 1.12-1.57; P =0.001). This association was significant even after adjustments were made for confounding factors. Conclusion Low urine SG was associated with increased risk of cardiac surgery associated AKI in patient with normal renal function. Evaluating preoperative urine SG may be useful in stratifying post cardiac surgery AKI risk.

P0628CREATININE-CYSTATIN C RATIO IS ASSOCIATED WITH MORTALITY IN ICU PATIENTS UNDERGOING CONTINUOUS RENAL REPLACEMENT THERAPY

Abstract Background and Aims Development of acute kidney injury (AKI) in intensive care patients considerably increases the risk of mortality. Although several factors that are related to outcome have been recognized in this patient group, stratifying mortality risk still remains a challenge. While serum creatinine levels are confounded by muscle wasting in critical illness, cystatin C is expected to be less modulated by muscle mass. Speculating that the ratio between serum creatinine and cystatin C may reflect muscle mass in critically ill AKI patients, we evaluated the association between creatinine-cystatin C ratio and mortality in patients requiring continuous renal replacement therapy (CRRT) in the intensive care unit (ICU). Method Retrospective analyses were conducted on 443 ICU patients who underwent CRRT between August 2009 and October 2016 at Severance Hospital of Yonsei University Health System, Seoul, South Korea. The patients were divided into four groups based on creatinine-cystatin C ratio at the time of CRRT commencement. The primary outcome was 90-day mortality after CRRT initiation. Results The mean age was 64 ± 15 years, and 57.3% of patients were male. The most common cause of AKI was sepsis. The median and range of the creatinine-cystatin C ratio was 0.83 (0.13-6.20). The 90-day mortality rate for each creatinine-cystatin C ratio quartiles 1, 2, 3, and 4 were 76.6%, 73.9%, 61.3%, and 51.8%, respectively. Multiple Cox proportional hazard models revealed that the creatinine-cystatin C ratio was an independent predictor of 90-day mortality even after adjusting for confounding factors (Hazard ratio, 0.97; 95% confidence interval, 0.95-0.99, P&amp;lt;0.01). The prediction of mortality was significantly improved when creatinine-cystatin C ratio was considered compared to APACHE-II or SOFA scores alone. Conclusion Creatinine-cystatin C ratio is associated with mortality in ICU patients undergoing CRRT, and may be a practical marker in predicting survival among ICU patients with AKI.

Longitudinal Body Mass Index Trajectories and Incident Chronic Kidney Disease in the General Population: Community-Based Cohort Study

Objectives: Obesity is a risk factors for chronic kidney disease (CKD). However, the weight changes overtime and this was not well reflected in previous studies. Thus, this study performed to investigated the association body mass index (BMI) trajectories and incident CKD using group-based trajectory modeling. Subjects/Methods: 6,497 healthy subjects without medical comorbidities in the Korean Genome and Epidemiology Study were included in the analysis. Changes in BMI determined by trajectory modeling to accurately identify groups with similar trends of changes in BMI over time; decreasing BMI (slope of BMI per year (%)=-0.481, 95% CI, -0.482 to -0.480), stable BMI (slope=0.001, 95% CI, 0.001-0.002), and increasing BMI (slope=0.499, 95% CI, 0.498-0.501). The primary outcome of interest was incident CKD, which was defined as an estimated glomerular filtration rate of <60 mL/min/1.73m2 for two consecutive measurements. Results: During a 61,894.7 person-years, incident CKD occurred in 455 (7.0%) participants; 8.6, 6.5, and 8.2 per 1000 person-years across the trajectories, respectively ( P =0.005). The decreasing BMI group was associated with a 36% (hazard ratio [HR], 0.64; 95% CI, 0.48-0.85) and 29% (HR, 0.71; 95% CI, 0.52-0.98) lower risk of incident CKD in fully adjusted models compared with subjects with increasing BMI group. This association was evident particularly in overweight and obese subjects, while the significance was lost in underweight or normal weight group. Changes in BMI well correlated with changes in various metabolic parameters. Conclusions: Weight loss is associated with decreased risk of developing CKD in healthy individuals without comorbid diseases. Funding Statement: This study was supported by the Ministry for Health and Welfare, Republic of Korea [4845-301 and 4851-302], and also supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (grant number: HC15C1129). Declaration of Interests: No potential conflict interest relevant to this article were reported. Ethics Approval Statement: KOGES was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board of Yonsei University Health System’s Clinical Trial Center (approval number: 4-2016-0100).

Morphologic Restoration After Peroral Endoscopic Myotomy in Sigmoid-type Achalasia

Background/AimsAchalasia is a chronic, progressive motility disorder of the esophagus. The sigmoid-type achalasia is an advanced stage of achalasia characterized by severe dilatation and tortuous angulation of the esophageal body. Peroral endoscopic myotomy (POEM) has been reported to provide excellent clinical outcomes for achalasia, including the sigmoid type, but the restoration of esophageal morphology and function remain poorly described. The aim of our study is to investigate esophageal restoration after POEM for sigmoid-type achalasia.MethodsFrom 98 patients with achalasia who underwent POEM in the Yonsei University Health System from 2013 to 2018, we recruited 13 patients with sigmoid-type achalasia (7 male; mean age 53.3 years) and assessed morphological and manometric changes in the esophagus.ResultsClinical success (Eckardt score < 3) was achieved in all cases. After POEM, the average angle of esophageal tortuosity became more obtuse (91.5° vs 114.6°, P = 0.046), esophageal body diameter decreased (67.6 vs 49.8 mm, P = 0.002), and esophagogastric junction opening widened (6.4 vs 9.5 mm, P = 0.048). Patients whose esophageal tortuosity did not improve had longer durations of symptoms than patients with improvement (80.2 vs 636 months, P < 0.001). An absence of peristalsis was observed in all patients pre- and post-POEM.ConclusionsPOEM resulted in excellent clinical outcomes and morphologic improvement in sigmoid-type achalasia. These results suggest that the improvement of esophageal tortuosity through POEM reflects a reduced esophageal burden.

Fluctuations in Influenza Epidemics and Suicide Mortality: A Time-Series Regression of 13-Year Mortality Data

Background: There is insufficient evidence to conclude regarding the association between influenza infection and neuropsychiatric symptoms including suicidality. Aims: We explored the association between influenza infection and suicide rates in a large population using a time-series regression of 13-year mortality data. Method: Weekly suicides and influenza were analyzed using time series regression. Regression coefficient for suicide based on percentage change of influenza was calculated using a quasi-Poisson regression. Non-linear distributed lag models with quadratic function up to 24 weeks were constructed. Results: The association between influenza and suicide increased significantly up to 8 weeks post-influenza diagnosis. A significant positive association between influenza symptoms and suicide was observed from 2009, when a novel A(H1N1)pdm09 virus provoked a worldwide pandemic. No meaningful association between these factors was observed before 2009. Conclusion: There was a significant positive relationship between influenza infection and suicide after 2009, when a novel A(H1N1)pdm09 virus provoked a worldwide pandemic. Funding Statement: This study was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) and funded by the Ministry of Science and ICT (NRF-2018R1C1B5083722) (to SJJ). Declaration of Interests: The authors declare no conflicts of interest. Ethical Approval Statement: The data used in this study lacks personal information. The Institutional Review Board (IRB) of the Yonsei University Health System approved the current study design (IRB number: Y-2017-0100).

Surgical Outcomes of Dysphagia Provoked by Diffuse Idiopathic Skeletal Hyperostosis in Cervical Spine

Abstract INTRODUCTION Diffuse idiopathic skeletal hyperostosis (DISH)-related dysphagia is a rare clinical condition. Some studies have reported surgical resection of anterior osteophytes, but there was no treatment guideline. METHODS We retrospectively investigated 21 cases of DISH-related dysphagia in Yonsei University Health System from 2003 to 2018. Patient's symptom were measured by O’neil's dysphagia scale. Prevertebral soft tissue (PVST) was defined as the distance of tracheal posterior border to most anterior portion of vertebra. All data were gathered both before surgery and after 1-mo of follow-up. We compared the symptom improved group (n = 13) with not improved group (n = 8) by various clinical and radiographic parameter. RESULTS In improved group (n = 13), postoperative PVST was 7.5 ± 3.4 mm whereas in not improved group (n = 8), it was 3.3 ± 0.8 mm. If considered the presence of cricoid cartilage, postoperative PVST + PVST cricoid was 8.4 ± 3.3 mm in improved group and 3.1 ± 1.0 mm in not-improved group. Significant statistical difference (P-value &lt; .05) were noted in all. Area under curve (AUC) value of postoperative PVST was 0.889 (cutoff: 3.25 mm) and postoperative PVST + PVST cricoid was 0.942 (cutoff: 4.50 mm), respectively. CONCLUSION Surgical removal of anterior osteophytes in cervical DISH is an effective option. PVST is useful indicator in DISH-related dysphagia. Surgeons should take aim to make sufficient prevertebral space after surgery because it is highly related to symptom improvement

Highlights From the Circulation Family of Journals.

Highlights From the Circulation Family of Journals.