• Radiation Oncology Journal
• /
• v.15 no.1
• /
• pp.71-78
• /
• 1997

Purpose : To collect beam data for dynamic wedge fields using conventional measurement tools without the multi-detector system, such as the linear diode detectors or ionization chambers. Materials and Methods : The accelerator CL 2100 C/D has two photon energies of 6MV and 15MV with dynamic wedge an91es of 15o, 30o, 45o and 60o. Wedge transmission factors, percentage depth doses(PDD's) and dose Profiles were measured. The measurements for wedge transmission factors are performed for field sizes ranging from $4\times4cm^2\;to\;20\times20cm^2$ in 1-2cm steps. Various rectangular field sizes are also measured for each photon energy of 6MV and 15MV, with the combination of each dynamic wedge angle of 15o 30o. 45o and 60o. These factors are compared to the calculated wedge factors using STT(Segmented Treatment Table) value. PDD's are measured with the film and the chamber in water Phantom for fixed square field. Converting parameters for film data to chamber data could be obtained from this procedure. The PDD's for dynamic wedged fields could be obtained from film dosimetry by using the converting parameters without using ionization chamber. Dose profiles are obtained from interpolation and STT weighted superposition of data through selected asymmetric static field measurement using ionization chamber. Results : The measured values of wedge transmission factors show good agreement to the calculated values The wedge factors of rectangular fields for constant V-field were equal to those of square fields The differences between open fields' PDDs and those from dynamic fields are insignificant. Dose profiles from superposition method showed acceptable range of accuracy(maximum 2% error) when we compare to those from film dosimetry. Conclusion : The results from this superposition method showed that commissionning of dynamic wedge could be done with conventional dosimetric tools such as Point detector system and film dosimetry winthin maximum 2% error range of accuracy.

• Radiation Oncology Journal
• /
• v.16 no.3
• /
• pp.259-264
• /
• 1998

Purpose : This study was to evaluate the effectiveness of preoperative radiotherapy in maxillary sinus cancer. Materials and Methods : A retrospective analysis was done for 42 patients with maxillary sinus cancer who were treated with radiation with or without surgery from April 1986 to September 1996. There were 27 male and 15 female patients. Patients' age ranged from 24 to 75 years (median 56 years). Stage distribution showed 2 in T2, 19 in T3, and 21 in T4 lesions The histologic type was squamous cell carcinoma in 38, undifferentiated carcinoma in 1, transitional cell carcinoma in 1, and adenoid cystic carcinoma in 2 patients. All patients were treated with radiation initially with a dosage range of 50.4-70.2 Gy (median 70.2 Gy) before further evaluation of remnant disease. Eleven patients were given induction chemotherapy (2cycles of 5-fluorouracil and cisplatin) concurrently with radiotherapy. Six to eight weeks after radiotherapy with or without chemotherapy computerized tomography (CT) of paranasal sinus was taken to evaluate remnant disease. If the CT finding showed remnant disease, a Caldwell-Luc procedure was done to get the specimen of suspicious lesions. A radical maxillectomy was done if the specimen was proven to contain malignancy. In contrast periodic follow-up examination was done without any radical surgery if the tissue showed only granulation tissue. Follow-up period ranged from 3 to 92 months with a median 16 months. Results : Nine (21.4$\%$) patients showed complete response (CR) and 33 patients (78.6$\%$) showed persistent disease (PER) to initial radiotherapy. Among the 9 CR patients, 7 patients had no evidence of disease (NED), 1 patient had local failure, and 1 patient had regional failure. Among 33 PER patients, salvage total maxillectomy was done in 10 patients, and the surgery was not feasible or refused in 23 patients. Following the salvage radical surgery, 2 patients were NED and 8 patients were PER status. Overall and disease- free survival rate at 5 years was 23.1$\%$ and 16.7$\%$, respectively. The only factors associated with the overall survival rate was the response to radiotherapy (P<0.01). Conclusion : The only factors associated with the overall survival rate was the response to radiotherapy. We could omit a radical mutilating surgery by preoperative irradiation in 7 of 42 patients (21.4$\%$) so as to preserve their facial integrity.

• Radiation Oncology Journal
• /
• v.16 no.3
• /
• pp.303-310
• /
• 1998

Purpose : To evaluate the results of the treatment of locally advanced but resectable rectal cancers and to analyze prognostic factors. especially with the emphasis on the treatment time factor. Materials and Methods : There were 71 patients with rectal cancer who had been treated by curative surgical procedure and postoperative radiotherapy from August 1989 to December 1993. The minimum follow up period was 24 months and the median follow-up was 35 months Radiation therapy had been given by 6 MV linear accelerator by parallel opposing or four-box portals. Whole pelvis was treated up to 5040 cGy in most cases. Systemic chemotherapy had been given in 94$\%$ of the patients, mostly with 5-FU/ACNU regimen. Assessment for the overall and disease-free survival rates were done by life-table method and prognostic factors by Log-Rank tests. Results : Five-year overall survival, disease-free survival were 58.8$\%$ and 57$\%$, respectively. Two-year local control rate was 76.6$\%$. Stage according to Modified Astler-Coller (MAC) system, over 4 positive lymph nodes, over 6weeks interval between definitive surgery and adjuvant radiotherapy and over 7 days of interruption during radiotherapy period were statistically significant, or borderline significant prognostic factors. Conclusion : The treatment results of patients with rectal cancers are comparable to those of other large institutes. The treatment results for the patients with bowel wall penetration and/or positive regional lymph nodes were still discouraging for their high local recurrence rate for the patients with MAC 'c' stage diseases and high distant metastases rate even for the patients with node-negative diseases. Maybe more effective regimen of chemotherapy would be needed with proper route and schedule. To maximize postoperative adjuvant treatment. radiotherapy should be started at least within 6 weeks after surgery and preferably as soon as wound healing is completed. Interruption of treatment during radiotherapy course affects disease-free survival badly, especially if exceeds 7 days. So, the total treatment period trout definitive surgery to the completion of radiotherapy should be kept as minimal as possiable.

• Korean Journal of Food Science and Technology
• /
• v.37 no.6
• /
• pp.882-888
• /
• 2005

Procedure for analysis of methylmercury in fish was developed, involving addition of HCl, extraction with toluene, and clean-up using L-cystein solution. Obtained extract is analyzed by gas chromatography with electron capture detector using Ulbon HR-Thermon-Hg column. Detection limit and recovery of the method were 0.005mg/kg (expressed as Hg), 98-107 (103%), respectively. Total mercury and methylmercury concentrations in 175 commercial fish samples ranged from [mean-max (mean), unit: mg/kg]: 0.014-1.200 (0.270) and 0.006-0.901 (0.168) in tuna-fish, 0.020-0.934 (0.323) and 0.012-0.553 (0.149) in martin-fish, 0.082-0.782 (0.391) and 0.040-0.436(0.201) in shark, 0,023-0.031 (0.026) and 0,013-0.018 (0.015) in salmon, 0.098-0.193 (0.133) and 0.031-0.015(0.090) in tilefish, and 0,031-0.214 (0.089) and 0.016-0.093 (0.042) in canned tuna respectively. No sample of analyzed fish exceeded 1.0mg/kg wet wt., limit for methylmercury established by Codex. In all species examined, estimated weekly intake was lower than Provisional Tolerable Weekly Intake recommended by the JECFA (the Joint FAO/WHO Expert Committee on Food Additives).

• Clinical and Experimental Pediatrics
• /
• v.49 no.2
• /
• pp.167-172
• /
• 2006

Purpose : Palpable lymph nodes are common in the pediatric population, and most of them are either inflammatory or congenital. As the diagnostic evaluation, fine needle aspiration cytology (FNAC) is known to be more convenient and economical than tissue biopsy. We evaluated the usefulness of FNAC in children and adolescents. Methods : Four hundred and thirteen FNAC samples(M : F=1 : 1.15) were retrospectively analyzed in patients who were brought to Inha University Hospital, from August 1999 to August 2004. Results : The most common age group was 16-20 years of age(N=148, 35.8 percent). The cervical area was the most frequently involved site(N=310, 75 percent). Non-specific lymphadenitis was the most common(N=227, 54.9 percent), followed by the benign neoplasm(N=59, 14.2 percent). Malignant tumors were 18 cases(4.3 percent), and congenital diseases were found in 10 cases(2.4 percent). In inflammatory lesions, tuberculous lymphadenitis(N=22, 5.3 percent) was the most common with a histologic sensitivity of 90.9 percent. The peripheral blood and serologic studies were non-specific. Fifty nine percent(N=244) of lymphadenitis improved without specific management. Antibiotics were prescribed in 15.2 percent of lymphadenitis and lymphadenectomy was performed in 12.6 percent. Conclusion : Most of the enlarged lymph nodes in children and adolescents were benign. These results show FNAC is a safe, rapid and reliable diagnostic procedure for the appropriate differential diagnosis of enlarged lymph nodes in children and adolescents.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.9 no.4
• /
• pp.71-80
• /
• 2009

Although desire for living without hazardous damages grows these days, threats from natural disasters which we are currently exposed to are quiet different from what we have experienced. To cope with this changing situation, it is necessary to assess the characteristics of the natural disasters. Therefore, the main purpose of this research is to suggest a methodology to estimate the potential property loss and assess the flood risk using a regional regression analysis. Since the flood damage mainly consists of loss of lives and property damages, it is reasonable to express the results of a flood risk assessment with the loss of lives and the property damages that are vulnerable to flood. The regional regression analysis has been commonly used to find relationships between regional characteristics of a watershed and parameters of rainfall-runoff models or probability distribution models. In our research, however, this model is applied to estimate the potential flood damage as follows; 1) a nonlinear model between the flood damage and the hourly rainfall is found in gauged regions which have sufficient damage and rainfall data, and 2) a regression model is developed from the relationship between the coefficients of the nonlinear models and socio-economic indicators in the gauged regions. This method enables us to quantitatively analyze the impact of the regional indicators on the flood damage and to estimate the damage through the application of the regional regression model to ungauged regions which do not have sufficient data. Moreover the flood risk map is developed by Flood Vulnerability Index (FVI) which is equal to the ratio of the estimated flood damage to the total regional property. Comparing the results of this research with Potential Flood Damage (PFD) reported in the Long-term Korea National Water Resources Plan, the exports' mistaken opinions could affect the weighting procedure of PFD, but the proposed approach based on the regional regression would overcome the drawback of PFD. It was found that FVI is highly correlated with the past damage, while PFD does not reflect the regional vulnerabilities.

• The Korean Journal of Pharmacology
• /
• v.14 no.1_2
• /
• pp.13-23
• /
• 1978

1) It was attempted to clarify the sites of action of central (either intraventricular or intracisternal) norepinephrine(NE) and clonidine to cause cardiac slowing and hypotension in urethane-anesthetized rabbits. 2) NE produced cardiac slowing but indistinct effect on blood pressure. Clonidine produced cardiac slowing and hypotension. 3) Intraventricular and intracisternal administration of NE, clonidine, phenylephrine and isoproterenol did not make difference in their effects, except that the onset of cardiac slowing by intracisternal NE was more rapid than intraventricular NE. 4) Upon repeated administration of NE at the intervals of about two hours, blood pressure responses changed to the pressor ones, the cardiac slowing unchanged. By this procedure the cardiac slowing as well as the hypotension by clonidine were gradually diminished. 5) Clonidine, when given during the NE effects were persisting, did not produce the lowering of blood pressure and further decrease of heart rate. NE, when given during the clonidine effects were persisting, produced marked elevation of blood pressure but did not produce further decrease of heart rate. 6) After intraventricular administration of regitine or desmethylimipramine, the cardiac slowing effect of NE and the clonidine effects were not observed, whereas NE produced marked elevation of blood pressure. 7) Reserpinized rabbits showed pressor and cardiac accelerating responses to NE; slight pressor, and little cardiac responses to clonidine. 8) It seems that the cardiac slowing by both clonidine and NE as well as the hypotetsion by clonidine are mediated by the presynaptic ${\alpha}$-adrenoceptor in the brain but the pressor responses to NE and clonidine are mediated by other site(s) than the presynaptic ones.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.10 no.1
• /
• pp.35-40
• /
• 2011

Purpose: This study was performed to evaluate the diagnostic usefulness of ankle stress radiograph for evaluation of chronic lateral ankle instability. Materials and Methods: Among patients undergoing the modified-Brostrom procedure, 42 cases with complete rupture of the anterior talofibular ligament were enrolled in this study. Sixty Korean adults (120 cases) were recruited as the control group. Radiologic measurement of talar tilt and anterior talar translation was performed through stress radiographs using Telos device. We obtained the normal range of Korean adults, and used as a standard value for judgment of mechanical instability. We analyzed the sensitivity, specificity, positive and negative prediction value of ankle stress radiograph. Results: On ankle stress radiograph, normal range of talar tilt angle and anterior talar translation was below $8.3^{\circ}$, below 7.6mm. Talar tilt angle on varus stress radiograph showed 57% of sensitivity, 97% of specificity, 89% of positive and 86% of negative prediction value. Anterior talar translation on anterior drawer stress radiograph showed 69% of sensitivity, 97% of specificity, 91% of positive and 90% of negative prediction value. Conclusion: Ankle stress radiograph had a good specificity, positive and negative prediction value for the evaluation of mechanical instability. However it underestimated the mechanical instability of ankle joint. It must be remembered that normal stress radiograph does not exclude ankle instability.

• The Journal of Korean Orthopaedic Ultrasound Society
• /
• v.2 no.1
• /
• pp.18-23
• /
• 2009

Purpose: To evaluate the relationship between the real pathology & abnormal finding found by ultrasonography. Without an MRI test being done beforehand, an arthroscopy is done after an ultrasonography to show abnormal lesions during a knee abnormality. Materials and Methods: The subjects were 42 patients out of 49 cases, excluding those with rheumatoid arthritis, septic arthritis and patients suspected with a ligament tear, which were examined by ultrasonography alone before receiving a knee arthroscopy in our hospital from July 2007 to July 2008. In every case, a physical examination, simple X-ray and knee ultrasonography was done. An arthroscopy was performed when there was ultrasonographic abnormal finding. Before the procedure, a MRI test was not performed and when abnormal findings were found by an arthroscopy, an appropriate surgery was done. Results: During the ultrasonographic examination, there were various sized effusions in the suprapatellar pouch. Also, in addition there were eleven cases of medial meniscus abnormalities, sixteen cases of lateral meniscus abnormalities, and two cases of cystic lesions. Throughout the arthroscopic examination, there were 14 cases of medial meniscus abnormalities, 20 cases of lateral meniscus abnormalities, 15 cases of cartilage damages, 9 cases of medial pathologic plica, 2 cases of intra-articular loose bodies, 5 cases of chondromalacia, 2 cases of cyst, and 2 cases of synovitis. When an effusion abnormality was found by the ultrasonography in a suprapatellar pouch, there was a 100% probability of knee pathology. When a medial meniscus abnormality was found with an ultrasonography, there was a 90.9% probability of a real pathology. When a lateral meniscus abnormality was found there was 81.2% probability of a real pathology. Ultrasonography was 100% accurate when it came to cystic lesions. Conclusion: Knee ultrasonography performed before an arthroscopy seems to be a very useful examination method when suspecting intra-articular lesions.

• The Journal of Korean Orthopaedic Ultrasound Society
• /
• v.3 no.2
• /
• pp.54-58
• /
• 2010

Purpose: In patients with chronic cervical pain, the facet joint is the source of the majority. Due to the difficulty of identifying the exact location of the joint that causes these symptoms, the possibility of complications and the placebo effect brings clinical application into question. In this study, we assessed the prevalence of patients with chronic cervical pain and report the diagnostic and therapeutic usefulness of ultrasonography - guided facet joint block therapy. Materials and Methods: Patients with nonspecific chronic cervical pain for more than 6 months were selected. Patients with disc herniation, sciatica-related pain were excluded from the study and 160 patients who failed in conservative treatment (physical therapy, chiropractic therapy, medication) were included in the study. Diagnostic Ultrasonography-guided facet joint block was performed with 1% lidocaine, and after two weeks, Bupivacaine 0.25% was used in patients who tested positive for lidocaine. Patients with more than 75% pain reduction during movement after facet joint block were considered positive. Results: Among the 160 patients with chronic cervical pain, 96 patients(60%) had a positive reaction after facet block using lidocaine. Among the 64 patients with a negative reaction to lidocaine, 48 patients(75%) had a positive reaction to bupivacaine. There were 48 false positive patients(50%) who showed a positive reaction to lidocaine but a negative reaction to bupivacaine. The mean VAS of the total 160 patients before blocks was 8.5, after 2 weeks follow up it decreased to 2.7 (p = 0.001) and after 4weeks 3.6 (p = 0.001). The 8 patients as an initial improvement of symptoms are not satisfied with the procedure and the 3 patients had been worsened during observation, were showed pain relief after additional ultrasonography-guided facet joint block at 4th week. Conclusion: A single ultrasonography-guided block to chronic cervical pain patients has relatively low diagnostic value since high false positive rate. The twice facet joint blocks is thought to be a useful method for interventional pain management of patients with chronic cervical pain.