위장관 ; 메타분석: 한국에서 Helicobacter pylori 제균에 순차치료가 기존치료보다 우월하다

정준원 ( Jun Won Chung ),하민수 ( Min Su Ha ),윤성철 ( Sung Cheol Yun ),김정호 ( Jung Ho Kim ),이종준 ( Jong Jun Lee ),김윤재 ( Yoon Jae Kim ),김경오 ( Kyoung Oh Kim ),권광안 ( Kwang An Kwon ),박동균 ( Dong Kyun Park ),이동호 ( Do 대한소화기학회 2013 대한소화기학회지 Vol.62 No.5

Background/Aims: Conventional triple therapy (CT) for Helicobacter pylori infection fails in up to one-third of patients. Sequential therapy (ST) seem be more effective than CT in other countries. However, there is no systemic literature review that directly compares CT and ST in Korea. The aim of this study was to compare ST with CT for H. pylori infection in Korea. Methods: Six randomized, prospective controlled trials were used to compare 10-day ST and 7- to 14-day CT in treatment-naive patients with documented H. pylori infection in Korea. Pooled eradication rates and OR with 95% CI were calculated. Results: The intention-to-treat eradication rates of H. pylori involving 1,529 patients were 79.7% (95% CI, 76.8-82.5%) for ST (n=754) and 68.1% (95% CI, 64.8-71.4%) for CT (n=775) (OR, 1.838; p<0.001). The per-protocol eradication rate of H. pylori involving 1,366 patients was 86.4% (95% CI, 83.3-88.5%) for ST (n=682) and 76.0% (95% CI, 72.8-79.2%) for CT (n=684) (OR, 1.974; p<0.001). Conclusions: Ten-day ST was superior to CT in terms of eradicating H. pylori infection. Therefore, ST should be considered as a first-line therapy in Korea. However, ST did not achieve a sufficient eradication rate. More effective therapy should be developed. (Korean J Gastroenterol 2013;62:267-271)

원인불명 현성 위장관 출혈에서 이중풍선 소장내시경 양성 소견의 예측 인자

정준원 ( Jun Won Chung ),변정식 ( Jeong Sik Byeon ),최기돈 ( Kee Don Choi ),최귀숙 ( Kwi Sook Choi ),김병규 ( Benjamin Kim ),명승재 ( Seung Jae Myung ),양석균 ( Suk Kyun Yang ),김진호 ( Jin Ho Kim ) 대한장연구학회 2006 Intestinal Research Vol.4 No.2

목적: 원인불명 위장관 출혈에서 이중풍선 소장내시경의 진단율은 60.0-76.0% 정도로 보고되고 있다. 그러나 어떤 임상적 특징을 보이는 환자에서 출혈 병소를 찾을 가능성이 높은지에 대해서는 잘 알려져 있지 않다. 저자들은 현성 원인불명 위장관 출혈에서 이중풍선 소장내시경의 병변 진단 예측 인자에 대해 살펴보고자 하였다. 대상 및 방법: 흑색변이나 혈변으로 상부 위장관 내시경과 대장내시경 시행 후 원인을 찾지 못해 이중풍선 소장내시경을 시행한 현성 원인불명 위장관 출혈 환자 28명(남:여=16:12, 13-82세)을 대상으로 하였다. 의무기록을 통해 이중풍선 소장내시경으로 원인 병변을 찾은 환자들과 못 찾은 환자들의 임상 및 검사실 소견을 비교 분석하였다. 결과: 28명 중 21명(75.0%)에서 이중풍선 소장내시경으로 원인 병변을 찾을 수 있었으며, 혈관이형성, 다양한 궤양, 종양 등이 포함되었다. 병변을 찾은 군의 연령은 50.5±20.4세로 못 찾은 군의 52.4±19.8세와 차이가 없었고, 남녀비도 차이가 없었다(12:9 vs. 4:3). 내원 시 혈역학적 불안정, 마지막 흑색변 및 혈변에서 이중풍선 소장내시경 시행까지의 시간, 수혈량 및 혈색소 수치도 두 군 사이에 차이가 없었다. 출혈 병력 횟수는 병변을 찾은 군에서 2.1±1.1회, 못 찾은 군에서 1.4±0.5회로 출혈 횟수가 많은 경우 병변 진단율이 높은 경향을 보였으나 통계적 유의성은 없었다. 과거력상 첫 출혈 시점부터 이번 출혈까지의 출혈 유병 기간은 병변을 찾은 군에서 196.8±238.5일로 못 찾은 군의 15.5±13.7일에 비해 유의하게 길었다(p=0.04). 결론: 현성 원인불명 위장관 출혈에서 출혈의 유병 기간은 이중풍선 소장내시경을 통한 병변 진단을 예측할 수 있는 유용한 임상 지표였다. 따라서 오랜 기간에 걸쳐 여러 차례 출혈을 보인 환자에서 이중풍선 소장내시경은 우선적으로 고려될 수 있을 것으로 생각한다. Background/Aims: The most frequent indication of double balloon endoscopy (DBE) is obscure gastrointestinal bleeding (OGIB). The aim of the study was to evaluate the clinical factors predicting the detection of bleeding focus by DBE in patients with overt OGIB. Methods: Twenty eight patients (male:female=16:12, 13-82 years) with overt OGIB who underwent DBE were enrolled. Medical records were reviewed and analyzed. Results: Bleeding focus was found in 21 patients (75.0%). Age, gender, time interval between the last blood passage and DBE, transfusion amount, hemodynamic instability, and the number of past bleeding episodes were not different between patients whose bleeding focus was found by DBE and those whose bleeding focus was not found. Duration of bleeding was significantly longer in patients whose bleeding focus was found by DBE than those whose bleeding focus was not found (196.8±238.5 vs. 15.5±13.7 days, p=0.04). Conclusions: Duration of bleeding may be a useful clinical parameter which predicts the detection of bleeding focus by DBE in overt OGIB. (Intestinal Research 2006;4:95-100)

확대 대장 내시경에 따른 선구 형태와 Cyclooxygenase-2의 발현율

정준원 ( Jun Won Chung ),장혜숙 ( Hye Sook Chang ),명승재 ( Seung Jae Myung ),김태훈 ( Tae Hun Kim ),이영미 ( Young Mi Lee ),변정식 ( Jeong Sik Byeon ),양석균 ( Suk Kyun Yang ),김진호 ( Jin Ho Kim ) 대한내과학회 2008 대한내과학회지 Vol.74 No.4

목적: 확대 내시경으로 관찰한 대장 종양 선구 형태와 병리조직 결과가 연관성이 있으며 대장암 및 폴립증에서 cyclooxygenase-2 (COX-2) 활성이 증가한다는 사실이 알려져 있다. 그러므로 대장 폴립 선구 형태로 COX-2 발현 양상을 유추할 수 있다면, NSAID 치료 반응을 예측할 수 있어 임상적으로 유용할 것으로 기대된다. 저자 등은 대장 폴립 감별진단에 있어서 확대 내시경의 유용성을 알아보고, 대장 폴립의 선구 형태에 따른 COX-2의 발현 빈도를 알아보고자 하였다. 방법: 대장 폴립으로 서울아산병원을 내원한 36명(남:여=26:10, 연령 중앙값 55세)에서 발견된 41개의 폴립 병변에 대해 indigocarmine 색소를 이용한 확대 내시경을 시행하여 여섯 가지의 선구 형태로 분류하였다. 모든 병변에 대해 조직 생검을 하여 병리조직 검사와 RT-PCR을 이용한 COX-2 mRNA 발현 유무 조사를 시행하였다. 결과: 확대 내시경으로 관찰한 선구 형태에 따른 조직학적 소견은 신생물성 선종은 선구 형태 I과 II형에서 50% (2/4)이었고, 선종이나 암의 비율이 IIIL형 이상에서 94.5% (35/37)이었다. COX-2 mRNA의 발현율은 조직학적 소견이 악성으로 진행할수록 발현율도 증가하였다(p=0.022). 하지만 각각의 선구형태간의 COX-2 발현에는 통계학적 차이는 보이지 않았다. 결론: 확대 결장내시경을 통한 대장 폴립의 선구 형태에 따른 분류가 융모상 선종이나 조기 대장암 또는 유의성 폴립의 감별 진단에 있어서는 큰 의미가 없었으며, COX-2의 발현율 또한 조직학적 소견이 악성으로 진행할수록 높아지나, 폴립의 선구 형태에 따라서는 통계학적인 차이가 없어 임상적으로 중요한 폴립을 감별하는데 큰 의미를 보여주지 못하였다. 따라서 최근 확대 결장내시경이 대장 병변을 더 자세히 관찰하여 조직학적 소견을 미리 예측하기 위한 목적으로 사용되고 있으나, 실제적인 유용성에 대해서는 더 많은 연구가 필요하리라고 생각한다. Background/Aims: Magnifying colonoscopy (MC) was introduced for prediction of pathologic findings. However, cyclooxgenase-2 (COX-2) expression in colonic polyps according to pit pattern has not been reported before. The aims of this study were to evaluate the usefulness of MC for differentiating polyps and to analyze COX-2 mRNA expression in colon polyps according to pit patterns. Methods: We studied 36 patients (M:F=26:10; median age 55 years) who received endoscopic polypectomy at Asan Medical Center. The pit patterns were classified into six types (type I, II, IIIL, IIIS, IV, and V). The expression of COX-2 mRNA was determined by reverse transcription-polymerase chain reaction. Results: Among 41 polyps from 36 patients, 38 polyps were diagnosed as benign colon polyps, and 3 polyps were diagnosed as early colon cancer. In assessing the histologic findings according to pit patterns, non-adenomatous polyps were detected in 50% of type I and II patterns, and pre-malignant polyps were detected in 94.5% of type IIIL, IIIS, IV, and V patterns. COX-2 mRNA expression rate increased in parallel with histologic grade (p=0.022). However, this was not correlated with pit pattern. Conclusions: MC pit patterns provide detailed gross morphologic features. COX-2 mRNA expression rate, while related to histologic progression, is not related directly to pit pattern, but further study is needed.(Korean J Med 74:391-396, 2008)

위막성 대장염에 있어 구불결장경검사의 유용성: Clostridium difficile독소 검사와의 비교 및 예후와의 연관성을 중심으로

정준원 ( Jun-won Chung ),변정식 ( Jeong-sik Byeon ),최귀숙 ( Kwi-sook Choi ),김병규 ( Benjamin Kim ),권승현 ( Seung Hyun Kwon ),예병덕 ( Byong Duk Ye ),명승재 ( Seung-jae Myung ),양석균 ( Suk-kyun Yang ),김진호 ( Jin-ho Kim ) 대한장연구학회 2007 Intestinal Research Vol.5 No.1

Background/Aims: Pseudomembranous colitis (PMC) shows a diverse clinical course. The aim of this study is to evaluate the usefulness of sigmoidoscopy in PMC. Methods: Sigmoidoscopic findings and medical records were analyzed in 74 patients with PMC (male:female=38:36, 62±16 years). Sigmoidoscopic grades of PMC were classified into mild (n=45) when pseudomembrane covered <1/3 of lumen, moderate (n=18) when it covered 1/3-2/3 of lumen, and severe (n=11) when its extent was >2/3 of lumen. Results: In comparison to sigmoidoscopy, diagnostic sensitivity of enzyme immunoassay (EIA) for C. difficile toxin A was 29%. EIA sensitivity was 38% in mild, 28% in moderate, 0% in severe sigmoidoscopic grade (p=0.02). Risk factors for severe sigmoidoscopic grade were ileus, nasogastric tube insertion, and serum albumin below 2.3 g/dL. Initial treatment success rate was lower in severe grade (33%) than mild (96%) and moderate grade (83%) (p<0.01). One year mortality rate was lower in severe grade (17%) than mild (85%) and moderate grade (84%) (p=0.01). Old age and severe sigmoidoscopic grade were risk factors for death. Conclusions: Sigmoidoscopic severity grading may be useful in the prediction of prognosis in PMC patients. Sigmoidoscopy may also be useful in the diagnosis of PMC, especially in patients with severe PMC. (Intest Res 2007;5:45-51)

식도성 삼킴곤란을 동반한 다발성 뇌신경계 위축증

박혜원 ( Hye Won Park ),정훈용 ( Hwoon Yong Jung ),이단비 ( Dan Bi Lee ),김도훈 ( Do Hoon Kim ),정기욱 ( Kee Wook Jung ),정준원 ( Jun Won Chung ),최귀숙 ( Kwi Sook Choi ),최기돈 ( Kee Don Choi ),송호준 ( Ho June Song ),김진호 ( Ji 대한소화기기능성질환·운동학회 2008 Journal of Neurogastroenterology and Motility (JNM Vol.14 No.2

Dysphagia occurs frequently as an accompanying sign of neurodegenerative disorders. Degeneration of the dorsal vagal motor nucleus may cause esophageal dysphagia. Multiple system atrophy (MSA) is a progressive neurodegenerative disorder of unknown etiology. Dysphagia is one well-recognized complication of MSA and is closely related to the prognosis of patients. However, the swallowing function of patients with MSA has not been explored systematically. We experienced a 73-year-old male who had recurrent syncope with dysphagia. Neurologic examinations revealed a cerebellar dysfunction and autonomic function tests were abnormal. We diagnosed this case as MSA. The esophagogastroscopy was normal and the esophageal manometry revealed low pressure of the upper esophageal sphincter and lack of normal peristalsis. Barium esophagography showed ineffective primary peristalsis and weak tertiary peristalsis. We considered that diagnosis of dysphagia caused by degeneration of autonomic cranial nerves. (Kor J Neurogastroenterol Motil 2008;14:140-144)

내시경의 위암과 위궤양 영상을 이용한 합성곱 신경망 기반의 자동 분류 모델

박예랑,김영재,정준원,김광기,Park, Ye Rang,Kim, Young Jae,Chung, Jun-Won,Kim, Kwang Gi 대한의용생체공학회 2020 의공학회지 Vol.41 No.2

Although benign gastric ulcers do not develop into gastric cancer, they are similar to early gastric cancer and difficult to distinguish. This may lead to misconsider early gastric cancer as gastric ulcer while diagnosing. Since gastric cancer does not have any special symptoms until discovered, it is important to detect gastric ulcers by early gastroscopy to prevent the gastric cancer. Therefore, we developed a Convolution Neural Network (CNN) model that can be helpful for endoscopy. 3,015 images of gastroscopy of patients undergoing endoscopy at Gachon University Gil Hospital were used in this study. Using ResNet-50, three models were developed to classify normal and gastric ulcers, normal and gastric cancer, and gastric ulcer and gastric cancer. We applied the data augmentation technique to increase the number of training data and examined the effect on accuracy by varying the multiples. The accuracy of each model with the highest performance are as follows. The accuracy of normal and gastric ulcer classification model was 95.11% when the data were increased 15 times, the accuracy of normal and gastric cancer classification model was 98.28% when 15 times increased likewise, and 5 times increased data in gastric ulcer and gastric cancer classification model yielded 87.89%. We will collect additional specific shape of gastric ulcer and cancer data and will apply various image processing techniques for visual enhancement. Models that classify normal and lesion, which showed relatively high accuracy, will be re-learned through optimal parameter search.

고압변압기의 임펄스 시험시 등전위확보를 위한 접지시스템 연구

유청희(Ryu Chung-hee),정준원(Jung Jun-won),한성구(Han Sung-Gu),김용(Kim Yong) 대한전기학회 2009 대한전기학회 학술대회 논문집 Vol.2009 No.4

본 논문은 고압변압기의 Impulse시험시 시험실의 등전위 확보를 위한 접지시스템의 구성방법에 대해 연구하였다. 고압변압기의 검사시험은 구조 및 권선 저항 측정시험 등 여러 가지 시험이 진행되고 있는데, 시험실에서 수행되는 시험중 내전압시험과 절연저항시험 등을 수행할 때 절연파괴시 높은 전위차로 인해 발생되는 사고를 미연에 방지할 수 있도록 등전위 확보 방안과 접지시스템의 구성방법을 구축하였다. 이를 위해 변압기의 시험방법과 시험이 종류에 대해 연구하였고, 접지시스템을 구성하기위한 사전조사방법과 접지시스템의 설계방법, 그리고 등전위확보를 위한 구성방법에 대해 연구하였다. 또한, 시험실의 지질 특성 및 지층 구조를 분석 모델링 하였고, 과학적이고 체계적인 접지설계 엔지니어링과 시뮬레이션을 통하여 과도시점의 상태에 대해 과도전위에 대한 모델링을 하였다. 이러한 연구를 통해 실제 현장에 적용하여 설비를 구축하였고, 성능을 측정 및 분석한 결과 시험시 과도상태에서 발생하는 시험장비와 피시험품의 전위차발생으로 인한 파손과 시험의 오차를 최소한으로 줄일 수 있음을 확인하였다. 따라서, 고압변압기의 검사시험 및 고전압 시험에서 시험시 발생하는 과도시점에서 등전위 확보방안에 대해 본 논문을 통해 구성방법에 대해 제안하고자 한다.

증례 : 소화기 ; 흑색변을 주 증상으로 내원한 Cameron 궤양

이헌남 ( Heon Nam Lee ),정준원 ( Jun Won Chung ),김윤재 ( Yoon Jae Kim ),김의주 ( Eui Joo Kim ),박성근 ( Sung Keun Park ),오경용 ( Kyong Yong Oh ),이영준 ( Young Jun Lee ) 대한내과학회 2012 대한내과학회지 Vol.82 No.5

Cameron ulcers are gastric ulcers or erosions located at mucosal folds in patients with large hiatal hernias. Mechanical trauma, gastric acid injury, or ischemia can cause their formation. Cameron ulcers are frequently seen as incidental findings during upper gastrointestinal endoscopy. About half of patients with these lesions are asymptomatic. However, Cameron ulcers are related to iron deficiency anemia and gastrointestinal bleeding in some cases. Here, we report a case of Cameron ulcers presenting with melena, which was successfully treated with proton pump inhibitors and iron supplementation. (Korean J Med 2012;82:585-588)

원저 : 헬리코박터 파일로리의 3차 구제요법에서 리파부틴과 레보플록사신의 비교

정명호 ( Myung Ho Jeong ),정준원 ( Jun Won Chung ),이상진 ( Sang Jin Lee ),하민수 ( Minsu Ha ),정석후 ( Seok Hoo Jeong ),나선영 ( Sunyoung Na ),나병수 ( Byung Soo Na ),박성근 ( Sung Keun Park ),김윤재 ( Yoon Jae Kim ),권광안 ( Kwa 대한소화기학회 2012 대한소화기학회지 Vol.59 No.6

Background/Aims: There is increasing need for third-line therapy of Helicobacter pylori due to increasing level of antibiotics resistance. The aim of this study was to compare rifabutin and levofloxacin rescue regimens in patients with first- and second-line Helicobacter pylori eradication failures. Methods: Patients, in whom a first treatment with proton pump inhibitor-clarithromycin-amoxicillin and a second trial with proton pump inhibitor-bismuth-tetracycline-metronidazole had failed, received treatment with either rifabutin or levofloxacin, plus amoxicillin (1 g twice daily) and standard dose proton pump inhibitor. Eradication rates were confirmed with 13C-urea breath test or rapid urease test 4 weeks after the cessation of therapy. Results: Eradication rates were 71.4% in the rifabutin group, and 57.1% in the levofloxacin group, respectively. Although there was no significant difference in Helicobacter pylori eradication rates between two groups (p=0.656), rifabutin based regimen showed relatively higher eradication rate. Conclusions: Helicobacter pylori eradication rates of rifabutin- or levofloxacin-based triple therapy could not achieve enough eradication rate. Further studies would be needed on combination of levofloxacin and rifabutin-based regimen or culture based treatment. (Korean J Gastroenterol 2012;59:401-406)

합성곱 신경망을 활용한 위내시경 이미지 분류에서 전이학습의 효용성 평가

박성진,김영재,박동균,정준원,김광기,Park, Sung Jin,Kim, Young Jae,Park, Dong Kyun,Chung, Jun Won,Kim, Kwang Gi 대한의용생체공학회 2018 의공학회지 Vol.39 No.5

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.