• Current Optics and Photonics
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• v.4 no.4
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• pp.286-292
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• 2020

Imaging through multicore fiber (MCF) is of great significance in the biomedical domain. Although several techniques have been developed to image an object from a signal passing through MCF, these methods are strongly dependent on the surroundings, such as vibration and the temperature fluctuation of the fiber's environment. In this paper, we apply a new, strong technique called deep learning to reconstruct the phase image through a MCF in which each core is multimode. To evaluate the network, we employ the binary cross-entropy as the loss function of a convolutional neural network (CNN) with improved U-net structure. The high-quality reconstruction of input objects upon spatial light modulation (SLM) can be realized from the speckle patterns of intensity that contain the information about the objects. Moreover, we study the effect of MCF length on image recovery. It is shown that the shorter the fiber, the better the imaging quality. Based on our findings, MCF may have applications in fields such as endoscopic imaging and optical communication.

• Journal of Chest Surgery
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• v.39 no.12 s.269
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• pp.920-926
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• 2006

Background: Mortality and morbidity of anastomotic complications after esophagectomy have gradually decreased in recent years. However, swallowing difficulties and reflux symptoms after esophagogastrostomy continue to be a burden jeopardizing the quality of life. In the present study, we evaluated the quality of esophagogastrostomy by analyzing anastomotic stenosis and reflux esophagitis. Material and Method: A retrospective analysis was made in 74 patients who underwent esophagogastrostomy after esophagectomy by one surgeon between January 1995 and December 2004. 53 patients of them received endoscopic examination during follow-up($29{\pm}23.6$ months, range $5{\sim}111$ months). Reflux esophagitis and stenosis at anastomostic site were analyzed according to the techniques and locations of esophagogastrostomy. Result: The median age at the time of repair was $60.3{\pm}8.87$ years(range $39{\sim}81$ years). 23 patients received a hand-sewn esophagogastric anastomosis and 30 patients a circular stapled one. There was no significant statistical difference in terms of anastomotic stenosis(p=0.64) and reflux esophagitis(p=0.41) between the two groups. Cervical anastomosis was peformed in 26 patients and intrathoracic anastomosis in 27 patients. No significant statistical difference in anastomotic stenosis between the two groups was found(p=0.44), but reflux esophagitis was noted in 3 patients in the cervical anastomosis group and 14 patients in the intrathoracic anastomosis group(p=0.003). Conclusion: Cervical anastomosis was supposed to have a better quality of esophagogastrostomy by lowering the risk of reflux esophagitis. In the future, the comprehensive study including a patient's subjective symptom and Barrett's metaplasia should be performed in larger cases.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.18 no.1
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• pp.7-10
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• 2007

Unilateral vocal fold paralysis resulting in glottal incompetence can cause significant morbidity attributable to impaired speech, swallowing, and ability to protect the airway. The treatment of unilateral vocal cord paralysis has a long history, marked by technical innovations and improvements. These methods typically use endoscopic injection or implants to augment the volume of the affected vocal fold. The first known treatment, reported by Brunnings in 1911, was paraffin injection. The first thyroplasty medializing the paralysed vocal cord was performed by Payr in 1915 ; here, a cartilage door-flap was created from the thyroid ala to obtain better voice quality. In the 1970s, Isshiki systematized and developed the use of the external medialization by Payr. Later he modified his original technique, and achieved safer and better results. Many other methods were introduced for external medialization during the 1980s and 1990s. There has been couple of materials using for medialization laryngoplasty: silicone bloc, cartilage, goretex (polytetrafluoroethylene), titanium, etc. Among them, silicone bloc is the most popularly used material. Type I thyroplasty in combination with arytenoid adduction is a proven technique for medialization of the paralysed vocal fold. In this paper, personal experience for using silicone bloc type I thyroplasty : decision making and practical points, long-term results and complication of the procedure will be discussed.

• Korean Journal of Psychosomatic Medicine
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• v.26 no.1
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• pp.68-75
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• 2018

Objectives : Since pain in cancer patients is an important factor that greatly affects the quality of life and prognosis, many attempts have been actively made to reduce the pain. Despite continuous effort on reducing pain after Endoscopic submucosal dissection (ESD), research has not been done on psychological factors as much as on biological factors affecting pain. The objective of this study is to investigate the psychological factors affecting postoperative pain in gastric tumor patients who underwent gastric ESD. Methods : 91 gastric tumor patients who visited National Health Service Ilsan Hospital in Korean between May 2015 and June 2016, and received ESD were evaluated. Baseline characteristics including sociodemographic factors, anxiety, depression, and resilience were evaluated before the procedure. Multivariate logistic regression was done to analyze factors affecting postoperative pain. Results : The group with high postoperative pain showed lower alcohol consumption and higher depressive symptom scores than the group with low postoperative pain. Also, the group with high postoperative pain showed lower total resilience score with lower subtotal scores in self-control and positive item. Multivariate logistic regression analysis of the postoperative pain showed that patients with lower score in self-control of resilience [odd ratio (OR), 0.911 ; 95% CI, 0.854-0.971, p=0.004) reported more pain after ESD. Conclusions : This study showed that patients with lower self-control ability of resilience felt more pain after ESD. Among the psychological factors evaluated in this study, resilience of an individual seems to have effect on pain.

• Journal of Gastric Cancer
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• v.16 no.3
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• pp.182-190
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• 2016

Purpose: This study aimed to establish a large-scale database of patients with gastric cancer to facilitate the development of a nationalcancer management system and a comprehensive cancer control policy. Materials and Methods: An observational prospective cohort study on gastric cancer was initiated in 2010. A total of 14 cancer centers throughout the country and 152 researchers were involved in this study. Patient enrollment began in January 2011, and data regarding clinicopathological characteristics, life style-related factors, quality of life, as well as diet diaries were collected. Results: In total, 4,963 patients were enrolled until December 2014, and approximately 5% of all Korean patients with gastric cancer annually were included. The mean age was $58.2{\pm}11.5$ years, and 68.2% were men. The number of patients in each stage was as follows: 3,394 patients (68.4%) were in stage IA/B; 514 patients (10.4%), in stage IIA/B; 469 patients (9.5%), in stage IIIA/B/C; and 127 patients (2.6%), in stage IV. Surgical treatment was performed in 3,958 patients (79.8%), endoscopic resection was performed in 700 patients (14.1%), and 167 patients (3.4%) received palliative chemotherapy. The response rate for the questionnaire on the quality of life was 95%; however, diet diaries were only collected for 27% of patients. Conclusions: To provide comprehensive information on gastric cancer for patients, physicians, and government officials, a large-scale database of Korean patients with gastric cancer was established. Based on the findings of this cohort study, an effective cancer management system and national cancer control policy could be developed.

• Journal of Korean Traditional Oncology
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• v.14 no.1
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• pp.29-35
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• 2009

Approximately 10 percent of advanced stomach cancer patients have internal bleeding in their stomach. It is crucial to treat internal bleeding since it severely deteriorates patient's condition, and disturbs process of chemotherapy. There are hemostatic agents and dressing, radiotherapy, endoscopic ligation and coagulation, surgical methods to treat bleeding. However, these methods cannot be executed in some cases in which patient is in terminal stage or not in desirable condition to take these treatments. We are going to introduce a case of advanced gastric cancer patient having stomach bleeding who made a choice to take oriental medical treatments. The patient was on third stage of stomach cancer, had 3200cc of blood transfusion for five times. After diagnosed as not being able to have resection, he started to oriental medical treatments to stop bleeding. From March 28, 2009 to April 16, 2009, we administer 120cc Bojungikgi-tang gamibang to the patient in 90minutes after each meal. During 19days of having Bojungikgi-tang gamibang, we observed that the patient needed significantly lower amount blood transfusion, to 640cc. The patient improves in performance, and was able to eat more. Despite of short period of observation, this case indicates that Bojungikgi-tang gamibang treatment to the patient could work as hemostat, further improved quality of patient's life.

• Journal of Gastric Cancer
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• v.22 no.3
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• pp.220-234
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• 2022

Purpose: The incidence of adenocarcinoma of the esophagogastric junction (AEG) has increased in recent years, and the optimal surgical strategy for AEG remains highly controversial. We aimed to evaluate the safety and efficacy of proximal gastrectomy with double-tract reconstruction (PG-DT) for the treatment of patients with AEG. Materials and Methods: We retrospectively analyzed patients with Siewert type II/III AEG between January 2013 and July 2018. Clinicopathological characteristics, survival, surgical outcomes, quality of life (QOL), and nutritional status were compared between the PG-DT and total gastrectomy with Roux-en-Y anastomosis (TG-RY) groups. Results: After propensity score matching, 33 patients in each group were analyzed. There were no statistical differences between the 2 groups in terms of disease-free survival and overall survival. The surgical option was not an independent prognostic factor based on the multivariate analysis. In addition, no differences were found in terms of surgical complications. There were no significant differences in QOL assessed by the Visick grade, Gastrointestinal Symptom Rating Scale, or endoscopic findings. Furthermore, the long-term nutritional advantage of the PG-DT group was significantly greater than that of the TG-RY group. Conclusions: PG-DT is a safe and effective procedure for patients with local Siewert type II/III AEG, regardless of the TNM stage.

• Journal of Yeungnam Medical Science
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• v.20 no.2
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• pp.105-116
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• 2003

Definitely, treatment for gastric cancer is primarily surgical. Detection in early stage of disease and complete surgical resection is the best way to cure gastric cancer. If surgery is planned, careful preoperative evaluation and corrections of physiologic and psychologic abnormalities are essential to reduce perioperative morbidity or mortality. Basic principle of gastrectomy for gastric cancer is an en bloc resection of tumor with adequate margins of normal tissue and with regional lymph nodes and omental tissues. To complete these principles, regional lymph nodes and all omental tissues should be removed altogether during performing various types of gastric resection. The lymph node dissection is one of the most effective procedures for gastric cancer to achieve curative resection. The basic types of gastric resection are distal subtotal gastrectomy and total gastrectomy according to the condition of primary lesions and the status of lymph node metastases. When the primary lesion is located near the esophagogastric junction, it is sometimes hard for a surgeon to select adequate surgical method. Postoperative quality of life in a patient has become a very important factor to be considered in every step of surgical therapy. With increasing incidence of early gastric cancer, a number of surgical trials for limited surgery or endoscopic procedures have been performed, but the long-term clinical results should be carefully analyzed to define the clinical relevance of these new techniques. For patients with disseminated gastric cancer, a palliative procedure can be performed to improve quality of life of patients and to avoid immediate death due to the cancer-related complications.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.631-638
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• 2016

Radiation proctitis is a common complication after radiotherapy for pelvic malignant tumors. This study was conducted to assess the efficacy of novel almagate enemas in hemorrhagic chronic radiation proctitis (CRP) and evaluate risk factors related to rectal deep ulcer or fistula secondary to CRP. All patients underwent a colonoscopy to confirm the diagnosis of CRP and symptoms were graded. Typical endoscopic and pathological images, risk factors, and quality of life were also recorded. A total of 59 patients were enrolled. Gynecological cancers composed 93.1% of the primary malignancies. Complete or obvious reduction of bleeding was observed in 90% (53/59) patients after almagate enema. The mean score of bleeding improved from 2.17 to 0.83 (P<0.001) after the enemas. The mean response time was 12 days. No adverse effects were found. Moreover, long-term successful rate in controlling bleeding was 69% and the quality of life was dramatically improved (P=0.001). The efficacy was equivalent to rectal sucralfate, but the almagate with its antacid properties acted more rapidly than sucralfate. Furthermore, we firstly found that moderate to severe anemia was the risk factor of CRP patients who developed rectal deep ulcer or fistulas (P= 0.015). We also found abnormal hyaline-like thick wall vessels, which revealed endarteritis obliterans and the fibrosis underlying this disease. These findings indicate that almagate enema is a novel effective, rapid and well-tolerated method for hemorrhagic CRP. Moderate to severe anemia is a risk factor for deep ulceration or fistula.

• Journal of Biomedical Engineering Research
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• v.39 no.5
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• pp.213-219
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• 2018

Stomach cancer is the most diagnosed cancer in Korea. When gastric cancer is detected early, the 5-year survival rate is as high as 90%. Gastroscopy is a very useful method for early diagnosis. But the false negative rate of gastric cancer in the gastroscopy was 4.6~25.8% due to the subjective judgment of the physician. Recently, the image classification performance of the image recognition field has been advanced by the convolutional neural network. Convolutional neural networks perform well when diverse and sufficient amounts of data are supported. However, medical data is not easy to access and it is difficult to gather enough high-quality data that includes expert annotations. So This paper evaluates the efficacy of transfer learning in gastroscopy classification and diagnosis. We obtained 787 endoscopic images of gastric endoscopy at Gil Medical Center, Gachon University. The number of normal images was 200, and the number of abnormal images was 587. The image size was reconstructed and normalized. In the case of the ResNet50 structure, the classification accuracy before and after applying the transfer learning was improved from 0.9 to 0.947, and the AUC was also improved from 0.94 to 0.98. In the case of the InceptionV3 structure, the classification accuracy before and after applying the transfer learning was improved from 0.862 to 0.924, and the AUC was also improved from 0.89 to 0.97. In the case of the VGG16 structure, the classification accuracy before and after applying the transfer learning was improved from 0.87 to 0.938, and the AUC was also improved from 0.89 to 0.98. The difference in the performance of the CNN model before and after transfer learning was statistically significant when confirmed by T-test (p < 0.05). As a result, transfer learning is judged to be an effective method of medical data that is difficult to collect good quality data.