• Korean Journal of Artificial Intelligence
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• v.11 no.1
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• pp.17-24
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• 2023

With the continuous growth in the amount of data collected and analyzed, deep learning has become increasingly popular for extracting meaningful insights from various fields. However, hardware limitations pose a challenge for achieving meaningful results with limited data. To address this challenge, this paper proposes an algorithm that leverages the characteristics of convolutional neural networks (CNNs) to reduce the size of image datasets by 20% through smoothing and shrinking the size of images using color elements. The proposed algorithm reduces the learning time and, as a result, the computational load on hardware. The experiments conducted in this study show that the proposed method achieves effective learning with similar or slightly higher accuracy than the original dataset while reducing computational and time costs. This color-centric dataset construction method using image smoothing techniques can lead to more efficient learning on CNNs. This method can be applied in various applications, such as image classification and recognition, and can contribute to more efficient and cost-effective deep learning. This paper presents a promising approach to reducing the computational load and time costs associated with deep learning and provides meaningful results with limited data, enabling them to apply deep learning to a broader range of applications.

• Journal of Chest Surgery
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• v.45 no.1
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• pp.11-18
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• 2012

Background: The aim of this study is to evaluate the clinical and rhythm outcomes of atrial fibrillation (AF) ablation through a port access approach compared with sternotomy in patients with AF associated with mitral valve diseases. Materials and Methods: From February 2006 through December 2009, 135 patients underwent biatrial AF ablation with a mitral operation via either a port-access approach (n=78, minimally invasive cardiac surgery [MICS] group) or a conventional sternotomy (n=57, sternotomy group). To adjust for the differences in the two groups' baseline characteristics, a propensity score analysis was performed. Results: After adjustment, there were no significant differences in the two groups' baseline profiles. The cardiopulmonary bypass time was significantly longer (p=0.045) in the MICS group ($176.0{\pm}49.5$ minutes) than the sternotomy group ($150.0{\pm}51.9$ minutes). There were no significant differences (p=0.31) in the two groups' rate of reoperation for bleeding (MICS=6 vs. sternotomy=2, p=0.47) or the requirement for permanent pacing (MICS=1 vs. sternotomy=3). The major event-free survival rates at two years were $87.4{\pm}8.1%$ in the MICS group and $89.6{\pm}5.8%$ in the sternotomy group (p=0.92). Freedom from late AF at 2 years was $86.8{\pm}6.2%$ in the MICS group and $85.0{\pm}6.9%$ in the sternotomy group (p=0.86). Conclusion: Both the port-access approach and sternotomy showed tolerable clinical outcomes following biatrial AF ablation with mitral valve surgery.

• Journal of the Korean Society of Radiology
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• v.83 no.3
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• pp.658-668
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• 2022

Purpose To evaluate the effectiveness of the transradial artery approach (TRA) for treating malfunctioning arteriovenous fistulas (AVFs) in patients on hemodialysis. Materials and Methods A retrospective analysis was conducted in this single-center study of TRA endovascular procedures in 73 patients (43 male and 30 female; mean age of 67.4 years (range, 42-92 years) with malfunctioning AVFs, between January 2008 and April 2019. Patients' baseline and lesion characteristics, technical and clinical success, and complications were evaluated, and functional patency was analyzed using the Kaplan-Meier method. Results Radial artery approaches were successful in all patients. Angioplasty performed using the TRA achieved technical and clinical success rates of 98.6%(72/73) and 91.7%(67/73), respectively. The median primary patency time was 18.8 ± 15.9 months. The primary functional patency rates at 3, 6, and 12 months were 82.1%, 68.6%, and 63.9%, respectively. There were no major complications or adverse events, such as hand ischemia, related to the radial artery approach. Conclusion In selected cases, the TRA can be used complementary to the transvenous approach to treat malfunctioning AVFs.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1811-1815
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• 2014

Background: In clinical trials with no upper age limit, the proportion of older patients is usually small, probably reflecting the more conservative approach adopted by clinicians when treating the elderly. An exploratory analysis of elderly patients in the RECORD-1 Trial showed that patients ${\geq}$ 65 y.o. had superior median PFS than overall RECORD-1 population (5.4 months and 4.9 months, respectively). We investigated the efficacy, relative benefit and safety of Everolimus (EVE) as sequential therapy after failure of VEGFr-TKI therapy for older patients with metastatic renal cell cancer (mRCC), in daily practice. Materials and Methods: 172 consecutive IRB approved patients with mRCC (median age 65, M:F 135/37, 78% clear cell) who received salvage EVE at 39 tertiary institutions between October 2009 and August 2011 were included in this analysis. Some 31% had progressed on sunitinib, 22% on sorafenib, 1% on axitinib, 41% on sequential therapy, and 5% had received other therapy. Patients with brain metastases were not included and 95% of the patients had a ECOG (Eastern Cooperative Oncology Group) performance status (PS) of 0 or 1. Previous radiotherapy was an exclusion criterion, but prior chemotherapy was permitted. Adequate organ function and hematologic parameters were mandatory. EVE administration was approved by the institutional review board at each participating institution and signed informed consent was obtained from all patients. Results: Median time of the whole cohort to last follow-up was 3.5 months (range 0.4-15.2 months). Forty four percent were continuing to take EVE at last followup. There were 86 (50%) patients ${\geq}$ 65 y.o. and 86 (50%) <65 y.o. The percentage of patients who showed PR/SD was higher in the older group than in the younger one (5.9%/61.2% vs 1.2%/46.5%, respectively). Median survival of older patients was also significantly longer (3.5 +/- 0.31 vs 3.1 +/- 0.34, hazard ratio=0.45, CI; 0.255-0.802). Analysis using Cox regression model adjusted for gender, PS, number of metastases, site of metastases, histology, smoking history and age detected an association between age and PFS (p=0.011). The frequency of adverse events in elderly patients treated with EVE was no greater than that in younger patients, although such toxicity may have had a greater impact on their quality of life. Conclusions: Older patients should not generally be excluded from accepted therapies (mTOR inhibitors after failure of VEGFr-TKI therapy) for mRCC.

• Journal of Korean Foot and Ankle Society
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• v.24 no.2
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• pp.87-93
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• 2020

Purpose: This study evaluated the clinical results of surgical treatment with minimally invasive plate osteosynthesis for treating displaced intra-articular fractures of the calcaneus in comparison with conventional lateral extensile approach plate osteosynthesis. Materials and Methods: Of 79 cases of Sanders type II or III calcaneus fractures, 15 cases treated with the minimally invasive calcaneal plate (group M) and 64 cases treated with lateral extensile approach calcaneal plate (group E) were identified. After successful propensity score matching considering age, sex, diabetes mellitus history, and Sanders type (1:3 ratio), 15 cases (group M) and 45 cases (group E) were matched and the demographic, radiologic, and clinical outcomes were compared between the two groups. Results: The median time of surgery from injury was 2.0 days in group M and 6.0 days in group E (p=0.014). At the six months follow-up, group M showed results comparable with those of group E in radiographic outcomes. In the clinical outcomes, group M showed better postoperative American Orthopaedic Foot and Ankle Society (AOFAS) and visual analogue scale (VAS) scores than did group E (p=0.001, p=0.008). A greater range of subtalar motion was achieved at the six months follow-up in group M (inversion 20.0° vs. 10.0°, p=0.002; eversion 10.0° vs. 5.0°, p=0.025). Although there were no significant differences in complications between the two groups (1 [6.7%] vs. 7 [15.6%], group M vs. group E; p=0.661), there was only one sural nerve injury and no wound dehiscence and deep infection in group M. Conclusion: Minimally invasive plate osteosynthesis showed superior clinical outcomes compared with that of the conventional lateral extensile approach plate osteosynthesis in Sanders type II or III calcaneus fractures. We suggest applying minimally invasive plate osteosynthesis in Sanders type II or III calcaneus fractures.

• Korean Journal of Community Nutrition
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• v.21 no.3
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• pp.237-246
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• 2016

Objectives: To investigate the effect of a worksite-based dietary intervention program for the management of metabolic syndrome (MS) among male employees. Methods: A dietary intervention program combining individual and environmental approach was implemented targeting white-collar employees at a worksite located in Seoul for 10 weeks. Out of 104 employees having agreed to participate in the program, those having three or more out of five components of MS and having two components, including a waist circumference component were classified into "the high risk group" (n=41) and received group nutrition education and individual nutrition counseling three times each. The rest of the study subjects were considered as "the low risk group" (n=63). The food environment at the worksite, where both the high and low risk groups were exposed, was changed to promote healthy eating. Physical data including MS components were collected and a questionnaire on dietary behaviors was administered before and after the intervention. The data from the high risk group (n=17) and the low risk group (n=20), excluding the subjects ineligible for or failed to complete the study (n=67), were analyzed. The difference before and after intervention was tested for significance by Wilcoxon signed-rank tests. Results: Weight, body mass index (BMI), waist circumference, blood pressure, HDL-cholesterol, and HbA1c and the healthy dietary practice score improved significantly after intervention in the high risk group. The median number of MS components decreased significantly from 3.0 to 1.0 in the high risk group. In the low risk group, only HbA1c significantly decreased. Conclusions: The 10-week worksite-based dietary intervention program combining individual and environmental approach was found to be effective for managing MS of male employees.

• Korean Journal of Head & Neck Oncology
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• v.17 no.2
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• pp.179-184
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• 2001

Objective: The role of chemotherapy in locally advanced head and neck cancer has been established in nasopharynx and larynx as definitive therapy and organ preserving therapy, respectively. Oral cavity cancers are relatively uncommon and local recurrence is the main cause of treatment failure. We planned this retrospective study to evaluate the role of neoadjuvant chemotherapy in locally advanced oral cavity cancer patients. Materials and Methods: From 1988 March to 2001 February, locally advanced, previously untreated oral cavity cancer patients who received neoadjuvant chemotherapy were examined. Chemotherapy had been done in the following patients: Histologically proven squamous cell or poorly differentiated carcinoma, stage 3 or 4, and performance state 0-2 patients. Chemotherapy regimen consisted of cisplatin and infusional 5-fluorouracil. Response was evaluated after 2 cycles and in case of no response, definitive local therapy was done; otherwise 3 cycles was done before local treatment. Results: 48 patients were treated and 47 patients were evaluable for responses. Complete response rate was 6.4%(3/47) and partial response 80.0%(38/47), scoring overall response rate of 87.2%. Median time to progression was 27.0 months (95% CI : 0-58months) and overall 5 year survival was 54.8%. 5-year disease-free survival in the patients in remission after local treatment was 51.9%. In multivariate analysis, contributing factor to the survival were response to neoadjuvant chemotherapy and local treatment modalities. Extensive surgery was done in 10 patients and 25 patents (52.1%) was followed up with preserved function. With median follow-up of 57.0 months, 19 recurrences were detected, most of which were local or regional type. Conclusion: Neoadjuvant chemotherapy followed by local treatment in oral cavity cancer showed high response rate and was thought to be effective therapeutic approach especially in view of organ preservation.

• Clinical and Experimental Pediatrics
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• v.61 no.7
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• pp.210-216
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• 2018

Purpose: The present study aimed to evaluate progression and prognosis according to the palliation method used in neonates and early infants aged 3 months or younger who were diagnosed with pulmonary atresia with ventricular septal defect (PA VSD) or tetralogy of Fallot (TOF) with severe pulmonary stenosis (PS) in a single tertiary hospital over a period of 12 years. Methods: Twenty with PA VSD and 9 with TOF and severe PS needed initial palliation. Reintervention after initial palliation, complete repair, and progress were reviewed retrospectively. Results: Among 29 patients, 14 patients underwent right ventricle to pulmonary artery (RV-PA) connection, 11 palliative BT shunt, 2 central shunt, and 2 ductal stent insertion. Median age at the initial palliation was 13 days (1-98 days). Additional procedure for pulmonary blood flow was required in 5 patients; 4 additional BT shunt operations and 1 RV-PA connection. There were 2 early deaths among patients with RV-PA connection, one from RV failure and the other from severe infection. Finally, 25 patients (86%) had a complete repair. Median age of total correction was 12 months (range, 2-31 months). At last follow-up, 2 patients had required reintervention after total correction; 1 conduit replacement and 1 right ventricular outflow tract (RVOT) patch enlargements. Conclusion: For initial palliation of patients with PA VSD or TOF with severe PS, not only shunt operation but also RV-PA connection approach can provide an acceptable outcome. To select the most proper surgical strategy, we recommend thorough evaluation of cardiac anomalies such as RVOT and PA morphologies and consideration of the patient's condition.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.4037-4041
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• 2016

Background: Hepatocellular carcinoma (HCC) is a common cancer that is frequently diagnosed at an advanced stage. Transarterial chemoembolisation (TACE) is an effective palliative treatment for patients who are not eligible for curative treatment. The two main methods for performing TACE are conventional (c-TACE) or with drug eluting beads (DEB-TACE). We sought to compare survival rates and tumour response between patients undergoing c-TACE and DEB-TACE at our centre. Materials and Methods: A retrospective cohort study of patients undergoing either treatment was carried out from January 2009 to December 2014. Tumour response to the procedures was evaluated according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST). Kaplan-Meier analysis was used to assess and compare the overall survival in the two groups. Results: A total of 79 patients were analysed (34 had c-TACE, 45 had DEB-TACE) with a median follow-up of 11.8 months. A total of 20 patients in the c-TACE group (80%) and 12 patients in the DEB-TACE group (44%) died during the follow up period. The median survival durations in the c-TACE and DEB-TACE groups were $4.9{\pm}3.2$ months and $8.3{\pm}2.0$ months respectively (p=0.008). There was no statistically significant difference noted among the two groups with respect to mRECIST criteria. Conclusions: DEB-TACE demonstrated a significant improvement in overall survival rates for patients with unresectable HCC when compared to c-TACE. It is a safe and promising approach and should potentially be considered as a standard of care in the management of unresectable HCC.

• Journal of Chest Surgery
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• v.57 no.1
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• pp.62-69
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• 2024

Background: Cervical esophageal cancer is a rare malignancy that requires specialized care. While definitive chemoradiation is the standard treatment approach, surgery remains a valuable option for certain patients. This study examined the surgical outcomes of patients with cervical esophageal cancer. Methods: The study involved a retrospective review and analysis of 24 patients with cervical esophageal cancer. These patients underwent surgical resection between September 1994 and December 2018. Results: The mean age of the patients was 61.0±10.2 years, and 22 (91.7%) of them were male. Furthermore, 21 patients (87.5%) had T3 or T4 tumors, and 11 (45.8%) exhibited lymph node metastasis. Gastric pull-up with esophagectomy was performed for 19 patients (79.2%), while 5 (20.8%) underwent free jejunal graft with cervical esophagectomy. The 30-day operative mortality rate was 8.3%. During the follow-up period, complications included leakage at the anastomotic site in 9 cases (37.5%) and graft necrosis of the gastric conduit in 1 case. Progression to oral feeding was achieved in 20 patients (83.3%). Fifteen patients (62.5%) displayed tumor recurrence. The median time from surgery to recurrence was 10.5 months, and the 1-year recurrence rate was 73.3%. The 1-year and 3-year survival rates were 75% and 33.3%, respectively, with a median survival period of 17 months. Conclusion: Patients with cervical esophageal cancer who underwent surgical resection faced unfavorable outcomes and relatively poor survival. The selection of cases and decision to proceed with surgery should be made cautiously, considering the risk of severe complications.