Equipment-Based Image-Enhanced Endoscopy for Differentiating Colorectal Polyps

구자설 대한소화기내시경학회 2014 Clinical Endoscopy Vol.47 No.4

The use of colonoscopy for the screening and surveillance of colorectal cancer has increased. However, the miss rate of advanced colorectal neoplasm is known to be 2% to 6%, which could be affected by the image intensity of colorectal lesions. Image-enhanced endoscopy (IEE) is capable of highlighting lesions, which can improve the colorectal adenoma detection rate and diagnostic accuracy. Equipment-based IEE methods, such as narrow band imaging (NBI), Fujinon intelligent color enhancement (FICE), and i-Scan, are used to observe the mucosal epithelium of the microstructure and capillaries of the lesion, and are helpful in the detection and differential diagnosis of colorectal tumors. Although NBI is similar to chromoendoscopy in terms of adenoma detection rates, NBI can be used to differentiate colorectal polyps and to predict the submucosal invasion of malignant tumors. It is also known that FICE and i-Scan are similar to NBI in their detection rates of colorectal lesions. Through more effective and advanced endoscopic equipment, diagnostic accuracy could be improved and new treatment paradigms developed.

의식하 진정 대장내시경 검사를 위한 Midazolam과 Propofol 병합요법의 효용성

구자설,최재현,정성우,한우식,이종섭,임형준,진윤태,전훈재,이홍식,이상우,김창덕,류호상 대한소화기내시경학회 2007 Clinical Endoscopy Vol.34 No.6

Background/Aims: There is increasing interest in the use of propofol as a sedative agent for colonoscopy. We evaluated the safety and efficacy of the synergistic sedation with midazolam combined with low-dose propofol versus that of midazolam alone. Methods: A total of 56 patients from among those who underwent total colonoscopy between August 2004 and October 2004 were randomly assigned to one of three medication treatment groups. Group A (n=18) received low-dose midazolam (0.03 mg/kg IV) plus propofol, group B (n=19) received high-dose midazolam (0.07 mg/kg IV) plus propofol, and group C (n=19) received high-dose midazolam alone. The patients' vital signs were monitored throughout the course of the study. The recovery time and quality as well as the patients' comfort level were also assessed. Results: There were no significant differences in baseline characteristics among the treatment groups. There were also no differences in the duration and insertion time of the colonoscopy among the three groups. The patients' comfort level and cardiorespiratory parameters during colonoscopy were similar among the three groups. The sedation efficacy and recovery times were also similar among the three groups. Conclusions: Midazolam combined with low-dose propofol as a sedative for colonoscopy exhibits similar effects on safety, patient' comfort level and recovery time to those of midazolam alone. (Korean J Gastrointest Endosc 2007;34:298-303)

하부위장관 : 무증상 성인에서 대장 선종과 비만의 연관성

구자설,안재홍,김진남,박선민,윤익,김동일,정성우,임형준,이홍식,이상우,최재현,김창덕,류호상 대한소화기학회 2007 대한소화기학회 추계학술대회 Vol.2007 No.-

Evaluation of the feasibility of using calcium aluminate composite (CAC) and Acement as additives for regulated set cement

구자설,유승엽,김진만,최선미,오상윤,한동엽 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.11

This work aims to evaluate the feasibility of using calcium aluminate composite (CAC) manufactured from steel slag, quicklycooled with high pressure air, and Acement, produced from CAC and various additives including gypsum as enhancementsfor regulated set cement. To evaluate the performance CAC or Acement as the additives of regulated set cements, CAC andAcement were replaced for the commercially available calcium sulfoaluminate cement (CSA)-based rapid setting cement(RSC). The engineering properties of workability, strength, and elastic modulus of mortar and concrete phases were thentested. From the mortar tests, as the replacement ratio of CAC was increased, the compressive strength of the mortarsignificantly decreased because of reduced amounts of gypsum for ettringite formation. On the other hand, as the replacementratio of Acement including gypsum was increased, the compressive strength increased due to enhanced ettringite formation. From the test results, Acement displayed more favorable results as an additive for the rapid setting cement than CAC. CACcontinued to show good performance at less than 10% of replacement ratio. Concrete testing revealed that mechanicalperformances of compressive, tensile, and flexural strength and elastic modulus all improved by 10% with CAC replacementand by 20% with Acement replacement. However, the resistivity performances for freeze-thaw tests and carbonation slightlydecreased.

의식하 진정 내시경검사: Midazolam vs Propofol

구자설,최재현 대한소화기내시경학회 2011 Clinical Endoscopy Vol.42 No.2

Endoscopy is increasingly performed with the patient under conscious sedation in many countries. The majority of patients can be adequately and safely sedated during routine upper endoscopy and colonoscopy with a combination of a benzodiazepine and opioid. Midazolam is a water-soluble benzodiazepine that is characterized by a rapid onset of action and a shorter duration compared with that of the other drugs of the same class. The major side effect of midazolam is respiratory depression, which can be reversed by flumazenil, a benzodiazepine-specific antagonist. Propofol is a lipid-soluble agent that has the advantages of a more rapid onset of action and a shorter recovery time compared to that of midazolam. However, it should be used with caution since it can lead to hypotension and respiratory depression. Propofol can be safely and effectively administered by nonanesthesiology physicians and nurses provided that they have received adequate training. Two models have been proposed for the administration of propofol by endoscopists: nurse-administered propofol sedation (NAPS) and combination propofol (propofol plus other agents) sedation. In order to modify the pharmacological disadvantages of propofol, fospropofol sodium, a water-soluble prodrug of propofol, has recently been developed. In addition, new delivery systems have been devised: patient-controlled sedation and computer-assisted personalized sedation, in which the computer continuously monitors the patient’s condition and adjusts the dose of propofol accordingly. Endoscopists must have a thorough understanding of the medications used for endoscopic sedation and they must acquire the skills necessary for the treatment of cardiopulmonary complications. Therefore, it is necessary to develop a practice guideline pertaining to endoscopic sedation and also training programs for physicians and nurses in Korea. 내시경검사에 진정제를 사용하는 의식하 진정 내시경검사는 점차 증가하고 있으며 벤조다이아제핀과 아편유사제가 흔히 사용되었다. Midazolam은 다른 벤조다이아제핀계 약물보다 효과가 빠르게 나타나고 지속시간이 짧은 장점이 있으나 부작용으로 호흡억제가 발생할 수 있다. 그러나, 벤조다이아제핀 길항제인 flumazenil을 사용하여 midazolam의 호흡억제 효과를 감소시킬 수 있다. Midazolam과 아편유사제의 병합은 효과적이며 안전한 진정방법으로 일반적인 상부위장관 내시경과 대장내시경 검사에 적합하다. Propofol은 지용성으로 midazolam보다 진정 유도와 회복이 빠른 장점이 있으나 저혈압과 일시적 무호흡이 보고되어 주의가 필요하다. 내시경 의사의 감독 하에 적절하게 훈련받은 의료인에 의한 propofol 투여는 효과적이고 안전하며, propofol 투여 방법으로는 간호사가 환자를 감시하면서 propofol을 투약하는 nurse-administered propofol sedation (NAPS)과 propofol과 다른 약물을 병용하는 propofol 병합요법이 있다. 새로운 진정제로 propofol 전구 물질인 fospropofol이 개발되었으며 새로운 약물 투여 방법으로 propofol 주입을 환자 스스로 조절하는 patient-controlled sedation과 환자 상태에 따라 자동으로 약물을 조절하는 computer-assisted personalized sedation이 연구 중에 있다. 안전하고 효과적인 의식하 진정 내시경검사를 위하여 내시경 의사는 사용 약물에 대한 충분한 지식을 갖춰야 하고 발생할 수 있는 부작용에 대처할 수 있어야 한다. 이를 위해 국내 실정에 적합한 내시경검사 지침과 의사 및 간호사를 위한 교육 훈련 프로그램이 개발되어야 할 것이다.

포스터 전시 : 소화기 ; 반흔기 소화성 궤양 환자에서 Helicobacter pylori 제균율

구자설,이상우,정성우,한우식,이종섭,김인정,이홍식,최재현,김창덕,류호상,현진해 대한내과학회 2005 대한내과학회 추계학술대회 Vol.69 No.10

설사

구자설,최재현 대한소화기학회 2007 대한소화기학회 춘계학술대회 Vol.2007 No.-

담낭결석 환자에서 총담관결석 진단을 위한 내시경초음파검사의 유용성

구자설,이홍식,정성우,한우식,이종섭,임형준,이상우,최재현,김창덕,유호상 대한소화기내시경학회 2007 Clinical Endoscopy Vol.35 No.4

목적: 총담관결석은 대체로 담낭결석에서 이차적으로 발생한다. 내시경역행췌담관조영술(endoscopic retrograde cholangiopancreatography, ERCP)은 총담관결석의 진단과 치료를 위한 일반적인 시술방법이지만, 침습적인 시술로 여러 가지 합병증이 발생할 수 있다. 내시경초음파검사(endoscopic ultrasonography, EUS)는 담석의 진단에서 초음파검사(ultrasonography, US)나 전산화단층찰영(computerized tomography, CT)보다 진단능이 우수하고 ERCP보다 합병증 가능성이 낮은 검사법이다. 본 연구는 담낭결석 환자에서 총담관결석 진단을 위한 EUS의 유용성과 총담관결석의 임상적 생화학적 예측인자를 알아보고자 하였다. 대상 및 방법: 2003년 4월부터 2005년 3월까지 고려대학교 안산병원에 내원하여 복부초음파 검사에서 담낭결석을 진단받은 환자들 중 총담관결석이 의심되어 EUS를 시행받은 117명을 대상으로 의무기록을 후향적으로 조사하였다. ERCP나 수술 중 담관검사를 통하여 총담관결석 유무를 확진하였으며, 확진된 환자를 대상으로 총담관결석 진단을 위한 US, CT, EUS, ERCP의 민감도, 특이도, 양성예측치, 음성예측치를 분석하였다. 담낭결석 환자에서 총담관결석 양성 환자군과 총담관결석 음성 환자군으로 구분하여 임상적 특징과 생화학적 검사 결과를 비교하였다. 결과: 총 117예에서 EUS를 시행하였고 시술과 관련된 합병증은 발생하지 않았으며, 이 중 23예(19.7%)에서 총담관결석이 관찰되었다. 총 117예 중 62예에서 ERCP나 수술 중 담관검사에서 총담관결석 유무가 확진되었고 총담관결석 진단에서 EUS의 민감도는 95%, 특이도는 95%, 양성예측치 91%, 음성예측치 98%였다. EUS와 ERCP의 총담관결석 진단 일치도는 94.8%로 나타났다(κ=0.887, p<0.01). 총담관결석 양성 환자는 총담관결석 음성 환자보다 연령이 많았고, 발열, 황달, 담관염 빈도가 높았다. 그리고, 총담관결석 음성군보다 양성군에서 간기능 이상이 흔히 관찰되었다(p<0.05). 결론: 총담관결석 진단에서 EUS는 높은 정확도를 보이는 비교적 안전하고 유용한 검사로 향후 진단 목적의 ERCP를 대체할 수 있을 것으로 생각되며, 총담관결석 의심 환자에서 임상적 특징과 검사 결과에 따라 선택적으로 EUS를 시행하는 것이 유용할 것으로 생각한다. Background/Aims: CBD stones (CBDS) are generally thought to originate from the gallbladder. Recently, EUS appears to be the best imaging method for making the diagnosis of CBDS. We conducted this study to evaluate the role of EUS for detecting CBDS in patients with gallbladder stones (GBS) and to determine the parameters for predicting CBDS. Methods: From April 2003 to March 2005, 117 GBS patients were enrolled. The patients' clinical and laboratory findings and the radiologic findings of US, EUS, CT and ERCP were reviewed. The sensitivity, specificity, PPV and NPV of EUS for detecting CBDS were evaluated by using ERCP and intraoperative CBD exploration as the gold standard for diagnosing CB. Results: A total 117 patients received EUS and no complications were encountered. After performing ERCP and/or intraoperative exploration, 62 of the patients were examined for determining the presence or absence of CBDS. EUS shows 95% sensitivity and 95% specificity for identifying CBDS. The overall agreement between EUS and ERCP was 94.8%. The patients with CBDS were older than those without CBDS. Fever, jaundice and cholangitis were more prevalent in the patients with CBDS. The results of liver function tests were elevated more frequently in the patients with CBDS (p<0.05). Conclusions: EUS is an accurate and minimally invasive method for diagnosing CBDS. Evaluating CBD in patients with gallstones is selectively recommended according to clinical and laboratory findings. (Korean J Gastrointest Endosc 2007;35:228-234)

포스터 전시 : 상부위장관 ; Amoxicillin 복용 방법에 따른 Helicobacter pylori 제균 효과

구자설,이상우,김승영,이범재,김동일,김세윤,정성우,이홍식,전훈재,최재현,김창덕,류호상 대한소화기학회 2006 대한소화기학회 추계학술대회 Vol.2006 No.-

비특이성 식도운동장애 환자에서 위식도역류질환의 유병률

구자설(Ja Soul Koo),송치욱(Chi Wook Song),조영직(Young Gik Jo),고동욱(Dong Wook Koh),손수민(Soo Min Shon),김용식(Yong Sik Kim),정록선(Rok Son Choung),진윤태(Yoon Tae Jeen),전훈재(Hoon Jai Chun),김창덕(Chang Duck Kim),류호상(Ho Sang R 대한소화기기능성질환·운동학회 2001 Journal of Neurogastroenterology and Motility (JNM Vol.7 No.2

N/A Backgroud/Aims: The nonspecific esophageal motility disorder (NEMD) has been reported to be related to gastroesophageal reflux disease (GERD) in some cases. However, the pathophysiologic mechanism of NEMD has not been estabilished. The aim of this study was to assess the prevalence of esophagitis and gastric acid reflux following abnormal contractions in patients with NEMD. Methods: 122 NEMD patients were enrolled (76 male and 46 female) and their endoscopic findings and 24 hour esophageal Ph data were compared with 24 healthy subj ects. The abnormal contractions were classified as 1) non-transmitted con-traction, 2) low amplitude contraction, 3) non-transmitted and low amplitude contraction, and 4) others. Results: Among the 122 patients with NEMD, 62 patients (50.8%) had GERD, 53 patients (43.4%) had endoscopic reflux esophagitis, and 41patients (33.6%) had both. Acid exposed time studied by 24 hour Ph monitoring was more increased in NEMD patients than in healthy controls (7.48 ±10.68 vs 1.42 ±1.17), but there were no differences among abnormal contraction patterns. Moderate to severe reflux esophagitis were frequently seen in patients with combined abnormal contractions as the results of endoscopic findings. Pre-existing factors for the gastric acid reflux in NEMD patients were male and esophageal hiatal hernia. Conclusions: Large numbers of NEMD patients were found to have concurrent GERD in our study. However, the esophageal peristaltic dysfunction was more closely related to the severity of esophagitis rather than to the amount of refluexed gastric acid itself. (Korean Journal of Gastrointestinal Motility 2001;7:168-174)