• The Journal of Korean Society for Radiation Therapy
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• v.1 no.1
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• pp.63-69
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• 1985

High energy electron beams took effect for tumor radio-therapy, however, had a lot of problems in clinical application because of various conversion factors and complication of physical reactions. Therefore, we had experimentally studied the important properties of high energy electron beams from the linear accelerator, LMR-13, installed in Yonsei Cancer Center. The results of experimental studies on the problems in the 8, 10, 12 Mev electron beam therapy were reported as following. 1. On the measurements of the outputs and absorbed does, the ionization type dosimeters that had calibrated by $^{90}Sr$ standard source were suitable as under $3\%$ errors for high energy electrons to measure, but measuring doses in small field sizes and the regions of rapid fall off dose with ionization chambers were difficult. 2. The electron energy were measured precisely with energy spectrometer consisted of magnet analyzer and tele-control detector and the practical electron energy was calculated under $5\%$ errors by maximum range of high energy electron beam in the water. 3. The correcting factors of perturbated dose distributions owing to radiation field, energy and material of the treatment cone were checked and described systematically and variation of dose distributions due to inhomogeneous tissues and sloping skin surfaces were completely compensated. 4. The electron beams, using the scatters; i.e., gold, tin, copper, lead, aluminium foils, were adequately diffused and minimizing the bremsstrahlung X-ray induced by the electron energy, irradiation field size and material of scatterers, respectively. 5. Inproving of the dose distribution from the methods of pendulum, slit, grid and focusing irradiations, the therapeutic capacity with limited electron energy could be extended.

• Journal of Radiation Protection and Research
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• v.48 no.2
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• pp.100-106
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• 2023

Background: As breast tissue expanders consist of metallic materials in the needle guard and ferromagnetic injection port, irradiation can produce radioactivation. Materials and Methods: A CPX4 (Mentor Worldwide LLD) breast tissue expander was exposed using the Versa HD (Elekta) linear accelerator. Two photon energies of 6 and 10 MV-flattening filter free (FFF) beams with 5,000 monitor units (MU) were irradiated to identify the types of radiation. Furthermore, 300 MU with 10 MV-FFF beam was exposed to the CPX4 breast tissue expander by varying the machine dose rates (MDRs) 600, 1,200, and 2,200 MU/min. To assess the instantaneous dose rates (IDRs) solely from the CPX4, a tissue expander was placed outside the treatment room after beam irradiation, and a portable radioisotope identification device was used to identify the types of radiation and measure IDR. Results and Discussion: After 5,000 MU delivery to the CPX4 breast tissue expander, the energy spectrum whose peak energy of 511 keV was found with 10 MV-FFF, while there was no resultant one with 6 MV-FFF. The time of each measurement was 1 minute, and the mean IDRs from the 10 MV-FFF were 0.407, 0.231, and 0.180 μSv/hr for the three successive measurements. Following 10 MV-FFF beam irradiation with 300 MU indicated around the background level from the first measurement regardless of MDRs. Conclusion: As each institute room entry time protocol varies according to the working hours and occupational doses, we suggest an addition of 1 minute from the institutes' own room entry time protocol in patients with CPX4 tissue expander and the case of radiotherapy vaults equipped with a maximum energy of 10 MV photon beams.

• Journal of Korean Academy of Nursing
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• v.25 no.2
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• pp.316-329
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• 1995

The purpose of this study was to exame the effectiveness of the hand massage as an independent nursing intervention for the cancer patients undergoing radiation therapy. The data were collected with quasiexperimental research design from 40 subjects-20 for experimental group and 20 for control group-of the radiation oncology department of one university hospital in Seoul from January 10th to March 29th, 1994. Subjects agreed to participate in this study and ranged in age from 18 to 82 years with mean age of 52.63. They had insight of their disease and had undergone radiotherapy at least twice. The hand massage developed by Mariah Snyder (1993) based on the Swedish Massage was administered to the experimental group prior to having radiation therapy at the waiting place of radiotherapy room. Hand massage was given to each hand of patient for five minutes once a day. Measurement of the patient's blood pressure, pulse rate, state anxiety and mood were done before and after the administration of hand massage for 5 days. The data were analyzed with paired t-test, t-test an4 the results were summarized as follows ; 1. After administration of the hand massage, the diastolic blood pressure of experimental group was decreased significantly, while the systolic blood pressure and the pulse rate were decreased, but not significantaly. 2. In the experimental group, the level of anxiety was significantaly lower than control group. The mean scores of the difference of the anxiety level after having hand massage was 8.60 in the experimental group and 0.75 in the control group. 3. The difference of the mood scores before and after the massage in the experimental group was decreased significantly. The mean mood score was decreased 4.80 in the experimental group as compared with 2.02 in the control group. 4. The patients after having the hand massage expressed subjectively their feeling of relaxation, well - being and being enjoyable, the significant decreased of physical symptoms and anxiety. The findings summarized that the use of the hand massage for the cancer patient undergoing radiation therapy Produced significant changes in the level of anxiety and relaxation. Therefore it is recommended to use the hand massage as an intervention for the patients.

• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.427-432
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• 1997

Re-188 is useful candidate for therapeutic radionuclide because it has a physical half life of 17 hours, contains beta emissions suitable for therapy(maximum energy 2.12MeV) and emits a gamma ray that is suitable for quantitative diagnostic scanning(155keV). To use Re-188 as a radionuclide compound of angioplasty balloon radiotherapy, we investigated the labelling method and biodistribution of Re-188-DTPA We postulated that labeled Re-188-DTPA is preferable because it would be excreted via urinary system more easily than other compounds. To label Re-188 with DTPA, 1ml of 222MBq(6mCi) of Re-188 was added to DTPA solution(DTPA 20mg, $SnCl_2{\cdot}2H_2O$ 10mg, pH 3.5) and boiled at $100^{\circ}C$ for 120min in water bath. pH was adjusted to 5 with 2.3% sodium acetate. Labeling efficiency was measured using TLC-SG(acetone, saline). We evaluated biodistribution of Re-188-DTPA in sacrificed mice at 10 and 60 minutes after injection. We acquired images of kidneys, and drew time-activity curves in normal dogs and rats and calculated Tmax and Tl/2 in rats. The labelling efficiency was 95.7% on average. Labelling of Re-188-DTPA was.stable(90% after 5hours) in vitro at room temperature. According to time-activity curves of dogs and rats, it took 15 to 20 minutes after injection for Re-188-DTPA to be washed out through kidneys. In conclusion, Re-188-DTPA was successfully labeled, Re-188-DTPA was stable in vitro and was excreted early via kidneys in animals. We could recommend Re-188-DTPA as radionuclide of potential use in angioplasty balloon radiotherapy.

• Journal of radiological science and technology
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• v.37 no.3
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• pp.223-231
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• 2014

Medical linear accelerator is widely used in radiation treatment field, and high energy photons, above 10 MV nominal accelerator voltage, are commonly utilized for the radiation treatment. However, these high energy photons lead the photo-nuclear reaction and the generation of photo-neutrons are accompanied. Thus, these problematic factors are issued in the view of radiation protection. Therefore, linear accelerator and radiation treatment room are simulated from MCNPX program in this study. The measurement points of interest are selected and analyzed, and the resulting effects derived from the properties of photo-neutron are evaluated. Therefore, we realized that the number of generating photo-neutrons was decreased by depending on the distance from the source. No matter what the nominal energy is set, the rates thermal neutrons to fast neutrons are marginal. It is founded that the amount of the thermal neutrons were decreased by depending on the distance from the source.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.101-106
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• 2000

Purpose : This study was peformed to evaluate the effectiveness and tolerance of craniospinal irradiation for patients with modulloblastoma and to define the optimal radiotherapeutic regimen. Materials and Methods : We retrospectively analyzed the records of 43 patients with modulloblastoma who were treated with external beam craniospinal radiotherapy at our institution between May, 1984 and April, 1998. Median follow up period was 47 months with range of 18 to U months. Twenty seven patients were male and sixteen patients were female, a male to female ratio of 1.7:1. Surgery consisted of biopsy alone in 5 patients, subtotal excision in 24 patients, and gross total excision in 14 patients. All of the patients were treated with craniospinal irradiation. All of the patients except four received at least 5,000 cGy to the posterior fossa and forty patients received more than 3,000 cGy to the spinal cord. Results : The overall survival rates at 5 and 7 years for entire group of patients were 57$\%$ and 56$\%$, respectively. Corresponding disease free survival rates were 60$\%$ and 51$\%$, respectively, The rates of disease control in the posterior fossa were 77$\%$ and 67$\%$ at 5 and 7 years. Gross total excision and subtotal excision resulted in 5 year overall survival rates of 76$\%$ and 66$\%$, respectively, In contrast, those patients who had biopsy alone had a 5 year survival rate of only 40$\%$. Posterior fossa was a component of failure in 11 of the 18 recurrences. Seven recurrences were isolated to the posterior fossa. Four patients had neuraxis recurrences, three had distant metastasis alone and four had multiple sites of failure, all involving the primary site. Conclusion : Craniospinal irradiation for patients with moduiloblastoma is an effective adjuvant treatment without significant treatment related toxicitles. There is room for Improvement in terms of posterior fossa control, especially in biopsy alone patients. The advances in radiotherapy including hypefractionation, stereotactic radiosurgery and 3D conformal radiotherapy would be evolved to improve the tumor control rate at primary site.

• Advances in pediatric surgery
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• v.10 no.2
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• pp.145-149
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• 2004

A 12-year-old boy with severe periumbilical pain visited the emergency room. Physical examination, abdominal ultrasonography, colonoscopy and CT, identified a lesion of sigmoid colon. Endoscopic biopsy showed a signet ring cell carcinoma of the sigmoid colon. On explorative laparotomy, cancer invasions of the adjacent structures and metastases on peritoneal wall were noticed. We performed palliative loop-ileostomy. He underwent chemotherapy and radiotherapy for 3 months. The second case was a 16-year-old boy with abdominal pain and hematochezia, transferred to our hospital with the diagnosis of acute appendicitis with periappendiceal abscess. Although he underwent appendectomy, the abdominal pain persisted. Digital rectal examination revealed a lumen-obstructing fungating mass in the rectum. Endoscopic biopsy revealed a adenocarcinoma. Cancer invasion of the adjacent structures and metastases involving the mesentery of the small intestine were found at laparotomy. A palliative procedure, a Hartmann's operation and end-colostomy at the sigmoid colon were performed. The patient died 8 month later due to pneumonia and sepsis. Chemotherapy was not applied.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.123-125
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• 2002

Blue light of Cherenkov radiation generated by electrons in transparent substances such as water and acrylic resin is well known generally. If students can easily observe the blue light at school, they may be impressed by the fascinating radiation. Four years ago, management of the Co-60 unit for radiotherapy was transferred to Nagoya University School of Health Sciences from a related hospital. We have examined whether or not the Cherenkov radiation in water from secondary electrons generated by Co-60 gamma-rays can be safely observed by eyes and photographs. First, the Cherenkov radiation in the water tank was led to the corridor outside the irradiation room by a mirror, and observed directly without any effect of the radiation exposure. Second, photographs of the Cherenkov radiation were taken under the conditions consisted of several irradiation fields and pass lengths of gamma-rays in water.

• Korean Journal of Head & Neck Oncology
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• v.33 no.1
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• pp.53-56
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• 2017

Pharyngocutaneous fistula is one of the most common wound complications after total laryngectomy. The leakage of saliva may cause an erosion of greater vessels nearby and result in a life-threatening bleeding. 65-year-old male received laryngectomy and pharyngectomy followed by Latissimus dorsi flap reconstruction due to recurred laryngeal cancer with oropharyngeal extension after postoperative radiotherapy. Pharyngeal fistula was developed and an excessive fresh blood flowed through the oral and nasal cavity. The patient was transferred to the operating room immediately, and the causing artery was ligated. The rupture of the common carotid artery and its branches should be warned when the pharyngocutaneous fistula is developed. Prompt and proper therapy must be performed for the patients with impending or acute hemorrhage.

• Journal of Chest Surgery
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• v.37 no.11
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• pp.929-932
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• 2004

The estimated relative incidence of primary pulmonary sarcoma to lung cancer is 0.4%. Furthermore, osteogenic sarcoma of the pulmonary artery is extremely rare. We report a case of a 63-year-old woman who visited our emergency room with the chief complaints of chest pain, dyspnea and dizziness. On echocardiography, right heart failure due to acute pulmonary artery embolism was diagnosed and we performed emergency operation. After opening the main pulmonary artery trunk, we found a mass attached to the arterial wall and massive thrombi around the mass. The mass was diagnosed as primary pulmonary artery osteosarcoma through postoperative evaluation. The patient received chemotherapy and radiotherapy. The patient is alive without specific symptoms 16 months postoperatively.