The purpose of this study has been performed to investigate the possibility of external audit program using thermoluminescence dosimetry for electron beam in korea. The TLD system consists of LiF powder, type TLD-700 read with a PCL 3 reader. In order to determine a calibration coefficient of the TLD system, the reference dosimeters are irradiated to 2 Gy in a (60)Co beam at the KFDA The irradiation is performed under reference conditions is water phantom using the IAEA standard holder for TLD of electron beam. The energy correction factor is determined for LiF powder irradiated of dose to water 2 Gy in electron beams of 6, 9, 12, 16 and 20 MeV (Varian CL 2100C). The dose is determined according to the IAEA TRS-398 and by measurement with a PTW Roos type plane-parallel chamber. The TLD for each electron energy are positioned in water at reference depth. In this study, to verify of the accuracy of dose determination by the TLD system are performed through a 'blind' TLD irradiation. The results of blind test are 2.98%, 3.39% and 0.01% (1sigma) at 9, 16, 20 MeV, respectively. The value generally agrees within the acceptance level of 5% for electron beam. The results of this study prove the possibility of the TLD quality assurance program for electron beams. It has contributed to the improvement of clinical electron dosimetry in radiotherapy centers.
Calibration ; Fibrinogen ; Korea ; Radiotherapy ; Water

PURPOSE: The aim of this study was to evaluate the effectiveness of our retraction method for achieving a good operative field for the adequate lymph node dissection during laparoscopic gastrectomy in view of short term surgical outcome. MATERIALS AND METHODS: This study prospectively enrolled 19 patients who underwent laparoscopic gastrectomy for early gastric cancer. The procedure was simply performed by putting the laparoscopic sigle suture in the phrenoesophageal ligament, and then the string was pulling and tying over the sternum. Surgical outcomes of these patients were evaluated. RESULTS: Under V-shaped liver retraction, the mean operating time and mean number of retrieved lymph nodes was 166.3 minute and 31.37, respectively. And the results were satisfactory compared to open or conventional laparoscopic gastric surgery. CONCLUSIONS: V-shaped liver retraction requires no extra port or assistant's hands, and prevents additional injury to any intra-abdominal organ. And this method can easily, efficiently and safely enable to achieve a good operative field for the lymph node dissection near the lesser curvature of the stomach.
Gastrectomy ; Hand ; Humans ; Laparoscopy ; Ligaments ; Liver ; Lymph Node Excision ; Lymph Nodes ; Prospective Studies ; Sternum ; Stomach ; Stomach Neoplasms ; Sutures

BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD) allows removal of colorectal epithelial neoplasms en bloc regardless of size. Colorectal ESD is a difficult procedure because of technical difficulties and risks of complications. This study aimed to assess the relationship between ESD outcome and degree of submucosal fibrosis. METHODS: Patients with colorectal tumors undergoing ESD and their medical records were reviewed retrospectively. The degree of submucosal fibrosis was classified into three types. The relationship between ESD outcome and degree of submucosal fibrosis was analyzed. RESULTS: ESD was performed in 158 patients. Thirty-eight cases of F0 (no) fibrosis (24.1%) and 46 cases of F2 (severe) fibrosis (29.1%) were observed. Complete resection was achieved for 138 lesions (87.3%). Multivariate analysis demonstrated that submucosal invasion of tumor and histology of carcinoma were independent risk factors for F2 fibrosis. Severe fibrosis was an independent risk factor for incomplete resection. CONCLUSIONS: Severe fibrosis is an important factor related to incomplete resection during colorectal ESD. In cases of severe fibrosis, the rate of complete resection was low even when ESD was performed by an experienced operator. Evaluation of submucosal fibrosis may be helpful to predict the submucosal invasion of tumors and technical difficulties in ESD.
Colorectal Neoplasms ; Fibrosis* ; Humans ; Medical Records ; Multivariate Analysis ; Neoplasms, Glandular and Epithelial ; Retrospective Studies ; Risk Factors

BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD) allows removal of colorectal epithelial neoplasms en bloc regardless of size. Colorectal ESD is a difficult procedure because of technical difficulties and risks of complications. This study aimed to assess the relationship between ESD outcome and degree of submucosal fibrosis. METHODS: Patients with colorectal tumors undergoing ESD and their medical records were reviewed retrospectively. The degree of submucosal fibrosis was classified into three types. The relationship between ESD outcome and degree of submucosal fibrosis was analyzed. RESULTS: ESD was performed in 158 patients. Thirty-eight cases of F0 (no) fibrosis (24.1%) and 46 cases of F2 (severe) fibrosis (29.1%) were observed. Complete resection was achieved for 138 lesions (87.3%). Multivariate analysis demonstrated that submucosal invasion of tumor and histology of carcinoma were independent risk factors for F2 fibrosis. Severe fibrosis was an independent risk factor for incomplete resection. CONCLUSIONS: Severe fibrosis is an important factor related to incomplete resection during colorectal ESD. In cases of severe fibrosis, the rate of complete resection was low even when ESD was performed by an experienced operator. Evaluation of submucosal fibrosis may be helpful to predict the submucosal invasion of tumors and technical difficulties in ESD.
Colorectal Neoplasms ; Fibrosis* ; Humans ; Medical Records ; Multivariate Analysis ; Neoplasms, Glandular and Epithelial ; Retrospective Studies ; Risk Factors

No abstract available.
Purpura* ; Thrombocytopenia*

BACKGROUND: The metabolic syndrome (MS) is a cluster of risk factors of cardiovascular disease. The association between components of the MS and bone mineral density has been researched, but no prior studies have directly evaluated the association with the metabolic syndrome and bone mineral density in Korea. METHODS: We evaluated postmenopausal women who had visited a university hospital from November 2006 to October 2007. Data on their lifestyle, current medical diseases and medications were collected from medical records. Height, body weight, waist circumference and serum lipid profiles were measured. RESULTS: The prevalence of metabolic syndrome was 21.8% in this study. In adjusted analysis including age and other factors, only waist circumference had a close correlation with bone mineral density of femur and lumbar vertebral body (P < 0.05). The bone mineral density of femur and lumbar vertebral body had no correlation with the presence of metabolic syndrome. When stratified by body mass index, corrected bone mineral density revealed no significant correlation with the presence of metabolic syndrome. CONCLUSION: The bone mineral density of postmenopausal women with metabolic syndrome has highly influenced by obesity, especially by abdominal obesity.
Body Height ; Body Mass Index ; Bone Density ; Cardiovascular Diseases ; Female ; Femur ; Humans ; Life Style ; Medical Records ; Obesity ; Obesity, Abdominal ; Osteoporosis ; Prevalence ; Risk Factors ; Waist Circumference

BACKGROUND: The metabolic syndrome (MS) is a cluster of risk factors of cardiovascular disease. The association between components of the MS and bone mineral density has been researched, but no prior studies have directly evaluated the association with the metabolic syndrome and bone mineral density in Korea. METHODS: We evaluated postmenopausal women who had visited a university hospital from November 2006 to October 2007. Data on their lifestyle, current medical diseases and medications were collected from medical records. Height, body weight, waist circumference and serum lipid profiles were measured. RESULTS: The prevalence of metabolic syndrome was 21.8% in this study. In adjusted analysis including age and other factors, only waist circumference had a close correlation with bone mineral density of femur and lumbar vertebral body (P < 0.05). The bone mineral density of femur and lumbar vertebral body had no correlation with the presence of metabolic syndrome. When stratified by body mass index, corrected bone mineral density revealed no significant correlation with the presence of metabolic syndrome. CONCLUSION: The bone mineral density of postmenopausal women with metabolic syndrome has highly influenced by obesity, especially by abdominal obesity.
Body Height ; Body Mass Index ; Bone Density ; Cardiovascular Diseases ; Female ; Femur ; Humans ; Life Style ; Medical Records ; Obesity ; Obesity, Abdominal ; Osteoporosis ; Prevalence ; Risk Factors ; Waist Circumference

BACKGROUND AND PURPOSE: Although thrombolytic strategies with streptokinase(STK) and tissue-type plasminogen activator(t-PA) in the treatment of acute myocardial infarction(AMI) have been studied in large-scale clinical trials in the western countries, such large-scale studies with urokinase(UK) are scanty. Even though UK is most commonly used thrombolytic agent for the treatment of AMI in Korea, there is no consensus on the dosage and the way of administration of UK in patients with AMI. Accordingly, a prospective clinical study was performed to evaluate the effects of thrombolytic strategies of intravenous double bolus method and standard double-infusion method with different dosage of UK in the treatment of AMI. SUBJECTS AND METHODS: Ninety there patients with AMI(male 75, female 18, age 57.5+/-10.8 years) were studied. The patients were divided into 3 groups according to dosage of UK and method of administration. Group I : 19 patients who received 1.5 million U of UK IV bolus, followed by 1.5 million U IV infusion for an hour(High Dose Group). Group II : 34 patients received 20,000U/kg body weight of UK IV bolus, followed by 20,000U/kg IV infusion for an hour(Double Dose Group). Group III : 40 patients received 1.5 million U of UK IV bolus and followed by 20,000U/kg IV bolus in 30 minutes with total dose of no more than 3 million U(Double Bolus Group). Coronary angiography(CAG) and left ventriculography(LVG) were performed 90 minutes after the administration of UK and post-AMI 7-10 days to investigate the patency of infarct-related artery(IRA) and LV function. Patency of IRA was graded according to the extent of flow of IRA. TIMI grade 0-1 was regarded as occluded, and grade 2-3 flow as patent. LV ejection fraction(EF) by echocardiography was measured on day 1, day 7-10 and 1 month after AMI. Indirect clinical parameters of thrombolysis were evaluated and were compared with CAG findings. RESULTS: 1) The 90 minutes IRA patency in Group III(Double bolus ; 79.0%) was higher than that in Group 1, but showed no statistically significant difference(High dose ; 61.5%, p=0.790). The 90 minutes IRA patency in Group III showed borderline significance with Group II(Double dose ; 57.1%, p=0.057). TIMI flow III in Group III(60.6%) was significantly higher than that in Group II(53.6%, p=0.0468) but showed no statistically significant difference with Group I(61.5%, p=0.158). 2) The EF by LVG were 49.1% in Group I, 41.7% in Group II and 49.2% in Group III. The difference in EF between Group I and Group III vs Group II was significant(p=0.008 in Group I, p=0.014 in Group III vs Group II). 3) Fatal bleeding complications(1 intracranial hemorrhage and 1 gastric ulcer bleeding) developed in Group II (Double dose). 4) Pain to door time, pain to needle time and door to needle time tended to be shorter in open(TIMI flow II-III) IRA group than in closed IRA group. 5) Initial EF were similar between open IRA group and closed IRA group(46.1% and 42.1% ; p=NS). The EF of open IRA group measured by LVG on initail coronary angiography(41.8% in closed IRA vs 48.0%, in open IRA, p=0.03) and by 2D-Echo on 7-10 day(41.7% in closed IRA vs 51.0% in open IRA, p=0.004) were better than those of closed IRA group. 6) Indirect clinical indices of reperfusion such as mean CPK peak, time to CPK peak significantly lower in open IRA group than in closed IRA group. 7) Fatal bleeding complications(1 intacranial hemorrhage and 1 gastric ulcer bleeding) developed in closed IRA group. CONCLUSION: The findings we observed in this trial showed that earlier initiation and more rapid infusion of UK were associated with more increased 90min patency of infarct-related artery and more improved LV function without any obviously increased bleeding complications or other serious life-threatening complications than conventional UK therapy. Specifically, double bolus IV injection of UK(1.5 million U bolus followed by 20,000 U/Kg bolus in 30min)was more effective method of thrombolysis than conventional method for achieving optimal reperfusion in AMI patients. Also, IRA patency at 90 minutes after the initiation of thrombolysis was important in preserving global LV function in early recovery phase of AMI. Further trials may be needed to determine more effective thrombolysis with UK in AMI.
Arteries ; Body Weight ; Consensus ; Echocardiography ; Female ; Hemorrhage ; Humans ; Intracranial Hemorrhages ; Korea ; Myocardial Infarction* ; Needles ; Plasminogen ; Prospective Studies ; Reperfusion ; Stomach Ulcer ; Urokinase-Type Plasminogen Activator*

We have designed the multi channel detector for the quality assurance of clinical photon beams. The detector was composed of solid phantom inserted by six plane-parallel ionization chambers at different depth. The chamber as a mini plane parallel chamber was made of carbon coated microfilms. In this study the electrical characteristics of the six chambers in the solid phantom were evaluated using 6 MV photon beam. The leakage currents were less than 0.5 pA, reproducibility was less than 0.5%, linearity was less than 0.5%, and dose rate effect was less than 0.7%. In addition the effect of dose variation from other chambers was estimated to maximum 0.8% approximately. The developed detector can be used for quality determination in output dosimetry or measurement of percentage depth dose approximately for clinical photon beam.
Carbon* ; Electrodes*

PURPOSE: To analyze the long-term stability of Farmer-type cylindrical ionization chambers by calibration factor provided from the KFDA (Korea Food Drug Administration) MATERIALS AND METHODS: The cylindrical ionization chambers used in this study were the PTW 30001 (30006), 30013, 30002, 30004, 23333, the Capintec PR06C, the NE 2571, the Exradin A12 and the Wellhofer FC65G (IC70). We were analyzed that the N(k) and N(D,W) calibration factor for the cylindrical chambers and compared between the measured N(D,W) and calculated N(D,W) calibration factor. RESULTS: We have observed that the long-term stability of the PTW 30013 (30006), the Wellhofer FC65G (IC70) and the NE 2571 has varied within 0.2%. The measured N(D,W) calibration factor was about 1.0% higher than the calculated N(D,W) that determined by the N(k) calibration factor. CONCLUSION: The study has evaluated that the long-term stability of the cylindrical chambers through analysis for the Nk and N(D,W) calibration factor. It has contributed to the improvement of clinical electron dosimetry in radiotherapy centers.
Calibration ; Radiotherapy