[en] In brachytherapy, it is important to determine the positions of the radiation sources which are inserted into a patients and to estimate the dose resulting from the treatment. Calculation of the dose distribution throughout an implant is so laborious that it is rarely done by manual methods except for model cases. It is possible to calculate isodose distributions and tumor doses for individual patients by the use of a microcomputer. In this program, the dose rate and dose distributions are calculated by numerical integration of point source and the localization of radiation sources are obtained from two radiographs at right angles taken by a simulator developed for the treatment planning. By using microcomputer for brachytherapy, we obtained the result as following 1. Dose calculation and irradiation time for tumor could be calculated under one or five seconds after input data. 2. It was same value under±2% error between dose calculation by computer program and measurement dose. 3. It took about five minutes to reconstruct completely dose distribution for intracavitary irradiation. 4. Calculating by computer made remarkly reduction of dose errors compared with Quimby's calculation in interstitial radiation implantation. 5. It could calculate the biological isoeffect dose for high and low dose rate activities

[en] Most pathologic conditions requiring emergent operation in neonate are congenital anomalies and delayed diagnosis and associated anomaly are important factors which have contributed to the high mortality rate of congenital anomalies. To prevent this delay, early recognition of the danger signals, adequate roentagenologic examination and accurate diagnosis should be made. Furthermore radiologists should be aware of developing mechanism, clinical manifestations and roentgenographic findings of those neonatal emergencies. 135 cases of neonatal emergencies were analyzed at this point of view, which verified by surgery and pathologic examination at Yonsei University College of Medicine, Severance Hospital since 1968. Embryology and characteristic roentgenographic pictures of each disease were discussed. The conclusions are as follows; 1. Most cases (110/135) presented intestinal obstruction. Imperforate anus (29 cases) was most common disease which followed by infantile hypertrophic pyloric stenosis (25 cases), small bowel atresia and stenosis (18 cases), congenital megacolon (15 cases) and esophageal atresia (14 cases). 2. Clinical Type and time of occurrence of symptoms and signs were so characteristic that these were helpful for differential diagnosis. 3. In infantile hypertrophic pyloric stenosis, confirmative diagnosis could be made in plain abdominal film, when 'Caterpillar sign' was seen. 4. When small bowel obstruction was suspected in plain abdominal film, barium enema examination was more helpful than upper G-I study. When microcolon was found, lower small bowel obstruction was highly suggested. 5. Diagnosis of midgut malrotation was possible in larger cases (4/7). Upper G-I examination was more valuable than barium enema study, because duodenal obstruction due to Ladd's band was common problem in neonate. 6. In neonatal period, diagnosis of aganglionosis could be made with the finding of barium stasis on 24-48 hours delay film, even though no demonstration of transition segment in barium enema study. 7. Imperforate anus and esophageal atresia had high incidence of associated anomalies and co-existency. So skillful inspection should be made for discovery of those associated anomalies

[en] A make-up of HANARO pool water was made through the reactor pool in the beginning. But it is now done through the service pool to reduce the impact to the hot water layer. The make-up of the pool water through the service pool was not easy, because an operator should control the valve manually, and it was hard to access the valve due to surrounding facilities. Therefore, it has been considered to return to a previous method to make up the pool water. This paper describes the behavior of the pool radiation and response of a radiation monitor located in a duct of the HVAC exhaust system around the reactor core when a pool water makeup is done through the reactor pool of HANARO

[en] The safety of procedure combined with wealth of information have resulted in rapid acceptance of CT as a practical and reliable neurodiagnostic technique. To understand the alternation in tissue density and associated displacement and distortion caused by pathologic lesion in CT, it is necessary to have clear understanding of normal anatomical landmark. For the purpose of establishing normartive criteria in Koreans for comparative diagnosis, 500 normal CT scan without neurologic sign were studied. The brief results are follows; 1. Among many ventricular index measured for lateral ventricle, the bifrontal CVI is more sensitive and easily determined. Ventricular size increased with age, especially after 6th decade but no difference with sex. 2. Mean width of third ventricle is 5mm( ± 0.3), more wider in male (male; 5.2mm, female; 4.5mm) and increased with age. 3. Mean width of fourth ventricle is 13mm( ± 1.3), without difference in age and sex. The shape of ventricle is variable form of triangle. The position of ventricle relative to Twining's line can be determined, so ratio of distance from tuberculum sellae to center of fourth ventricle to Twining's line is between 0.46-0.52. 4. Suprasellar cistern is visible in 89.7% of scan and shape of cistern is found to be pentagonal (73.3%), hexagonal (23.0%) and tetragonal (3.7%). 5. Choroid plexus can be identified in 90% and asymetrical in 4%. 45% of identified choroid plexus can be visible on scan without contrast enhancement, and more frequently visible in older age

[en] Thermoluminescent dosimeters (TLD) are nowadays widely used in radiation therapy to measure the radiation dose. We experimented the polymers to response in radiation and attempted to apply in clinical use, the polyethlene which is tissue equivalent material, instead of metallic substances. Polymers have the properties of thermoluminescence (TL) and thermally stimulated currents (TSC) which are due to several kinds of charged particles such as dipoles, electronic trapped charges and mobile ions. Several peaks are detected in the thermally stimulated current in polyethylene under bias field, V, by heating from room temperature to 100 .deg. C shortly after irradiation. As V increases, both the peak temperature T_m and the activation energy H decreases, while the peak current i_m increases. We plotted the T_m- V and I_m-V curves and calculated the election trap depth (H₀) with the recombination operative TSC theory and compared the peak TSC with radiation doses and energies

[en] The exophthalmos of Graves' disease remains a pathophysiologic and therapeutic puzzle. Its relation to the hyperthyroidism of Grave's disease is far from clarified. It is a common clinical observation that exophthalmos does not often relate temporally with the onset of hyperthyroidism. Furthermore, exophthalmos may occur in patients who have no evidence of thyroid disease. Pathologically, exophthalmos is characterized by marked lymphocytic infiltration of the retro-orbital muscles, with edema and mucopolysaccharide deposition. Recently, cellular immunity in response to retro-orbital antigens and abnormal humoral immunity are suggested for the pathogenesis of exophthalmos. We experienced 2 patients with hyperthyroidism and unilateral exophthalmos. The clinical and laboratory features of the patients are presented with review of articles, with emphasis on pathogenesis.

[en] These paper is an analyses of 110 patients who received abdominal aortography and selective organ angiography from July 1977 to August 1979 at the Department of Radiology of Yonsei Medical Center. 1. The most frequent site of bifurcation of the abdominal aorta was the 4th intervertebral disc level, occurring in 22 of 50 cases (42.3%). 2. The celiac trunk arose most frequently at the level of the 12th thoracic intervertebral disc, occurring in 11 of 52 cases (21.2%). 3. The superior mesenteric artery arose most frequent at the level of the upper third of the 1st lumbar vertebra, occurring in 8 of 30 cases (26.7%). 4. The right renal artery most frequently arose at the level of the middle third of the 1st lumbar vertebra, occurring in 17 of 70 cases (24.3%) and the left renal artery occurred most frequently in 1st lumbar vertebral disc level, 14 of 70 cases (20%). 5. Both renal arteries most commonly arose symmetrically as seen in 37 of 70 cases (52.6%). Case in which the rights arose at a higher level than the left occurred in 28 of 70 cases (40.6%). 6. Accessory renal arteries occurred in 19 of 70 cases (27.1%). 7. The most common form of the celiac trunk in which it divides into left gastric, splenic and common hepatic arteries was seen in 30 of 38 cases (78.9%). 8. The normal hepatic artery pattern in which it arise from the common hepatic artery and divides into right, middle and left hepatic artery occurred in 23 of 38 cases (60.5%0. A replaced right hepatic artery was seen in 2 of 35 cases (5.3%), and an accessory right hepatic artery also in 2 of 38 cases (5.3%).

[en] Interaction between high energy electrons and matters had many complex reactions and the high energy electrons lost their energies with collision and scattering, therefore, electrons distribution in matters was shown as various situation by scattering, exciting and ionizing with molecular. We experimentally studies with 13 MeV Linear Accelerator and thermoluminescence dosimeter using aluminium and Teflon, etc., and measured energy loss of electrons, electron range, electron scattering and dose distribution in matter. We compared the results with theoretical formular, between 4-qw MeV, the energy loss of electrons was decreased by 2 MeV per 1g/cm² but under 1MeV it was rapidly decreased. Electron range in matter reached to 0.5/cm² per 1MeV of incident energy at 6-12MeV. The dose distribution in matter was increased slightly to some depth by total distribution i.e., the combined intensity of primary and secondary radiant and it was rapidly decreased near the maximum range of electrons. Energy loss of electrons and electron range measured by experiment were coincided with theoretical equations of L. Landau and Feather under 5 and 3% errors respectively. The dose distribution of electrons in matter was similar to L.V. Spencer formular, however, we had found that it was quite different in accordance with the field size and that new formular of dose distribution was induced as empirical function contained experimental factors according to field size

[en] We studied for the shielding materials of normal tissue in high energy election irradiation. The lead plate has being chosen as the appropriate shielding material and the dose distribution is transformed into following: 1) The thickness of lead for complete shielding of high energy election is 3.2 mm Pb for 8 MeV 4.3 mm Pb for 10 MeV 5.0 mm Pb for 12 MeV 2) Surface dose is increased about 3 to 10 percent of maximum dosage, if the lead plate is used for electron beam shielding. 3) The Bremsstrahlung is occurred from shielding lead plate from above 4 to 6 percent of maximum dosage, yet this dosage is not above the practical error of radiotherapy.

[en] Shoulder arthrogram and dissection in cadaver were performed for clinical application. Puncture site for contrast injection was studied. The results were as follows: 1. Shoulder joints is located above the axillar and arthrography of shoulder is a simple, safe and easily interpreted. 2. The land mark for injection is a point 1.5 cm below the tip of coracoid process and very slightly medial to it. 3. There were contrast material leak from subscapular recess and distal end of the synovial sheath surrounding the long head of the biceps tendon in normal shoulder arthrogram. 4. Synoviad cavity margin show smoothness and no abnormal filling defect. 5. There were no communication between synovial cavity and subdeltoid bursa. 6. There were no specific anatomic variation in shoulder joint