• The Journal of Korean Society for Radiation Therapy
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• v.35
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• pp.33-39
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• 2023

Purpose: The purpose of this study is to find out the dose variation according to thickness of the air gap between the patient's body surface and immobilization device in the treatment plan. Materials and Methods : Four conditions were created by adjusting the air gap thickness using 5 mm bolus, ranging from 0 mm to 3 mm bolus. Immobilization was placed on top in each case. And computed tomography was used to acquire images. The treatment plan that 430 cGy (Relative Biological Effectiveness,RBE) is irradiated 6 times and the dose of 2580 cGy (RBE) is delivered to 95% of Clinical Target Volume (CTV). The dose on CTV was evaluated by Full Width Half Maximum (FWHM) of the lateral dose profile and skin dose was evaluated by Dose Volume Histogram (DVH). Result: Results showed that the FWHM values of the lateral dose profile of CTV were 4.89, 4.86, 5.10, and 5.10 cm. The differences in average values at the on the four conditions were 3.25±1.7 cGy (RBE) among D_95% and 1193.5±10.2 cGy (RBE) among D_95% respectively. The average skin volume at 1% of the prescription dose was 83.22±4.8%, with no significant differences in both CTV and skin. Conclusion: When creating a solid-type immobilization device for carbon particle therapy, a slight air gap is recommended to ensure that it does not extend beyond the dose application range of the CTV.

• Korean Journal of Ichthyology
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• v.2 no.1
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• pp.53-62
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• 1990

Morphological development from egg to juvenile stages of the trident goby, Tridentigertrigonocephalu5 were observed in the laboratory at Pusan, Korea. The ripe eggs were spherical in shape, measuring 0.49-0.62 mm in diameter. The eggs became ellipsoid shape after the insemination and measured about 1.40-1.58 mm on the long axis. Hatching began about 158 hours after insemination at water temperature of $20.5-24^{\circ}C$. The newly hatched larvae were 2.88-3.14 mm in total length(TL), with 27-28(10+ 17-18) myomeres. Many melanophore and guanophores are distributed on eye cups, gas bladder, optic vesicle, intestine and the caudal region. Three days after hatching the yolk and oil-globule was completely absorbed and the larvae attained a total length 3.26-3.62 mm. The larvae swam actively in the aquarium and fed on the rotifer. Ten days after hatching, the larvae averaged 5.20 mm in TL and the caudal notochord flexed at $45^{\circ}$. Twenty days after hatching, the larvae averaged 7.47 mm in TL and rudimental anal, second dorsal, caudal and pectoral fins were formed. The larvae attained 12.05-12.65 mm in TL thirty five days after hatching and are found to transit the bottom-life, and first dorsal and ventral fins are completely formed. The larvae reached the juvenile stage at 45-50 days after hatching and attained 15.85-16.95 mm in TL, and all scales appeared on the body.

• Korean Journal of Ichthyology
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• v.3 no.1
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• pp.1-10
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• 1991

Spawning behavior and development of eggs and larvae of Mugilogobius abei were observed in the laboratory at Pusan, Korea. The adult male of Mugilogobius abei was observed making nest-like spawning-bed to lay eggs and showing territorial and courtship behaviors. The eggs were transparent and spherical in shape, measuring 0.40~0.50 mm in diameter. They have a bundle of adhesive filaments at their basal end and a cluster of small oil globules. The eggs became ellipsoid shape after the insemination and measured about 0.93~0.96 mm on the long axis. Hatching began about 110 hours after fertilization at water temperature of $24.5{\sim}25.5^{\circ}C$. The newly hatched larvae were 2.04~2.10 mm in total length, with 24~25(8~9+16) myomeres. Many melanophore and guanophore are distributed on eye cups, gas bladder, optic vesicle and the caudal region. Four days after hatching the yolk and oil-globule were completely absorbed and the larvae attained a total length 2.20~2.35 mm. The larvae swam actively in the aquarium and start to practice feeding on the rotifer. Twelve days after hatching, the larvae averaged 3.20 mm in TL and the caudal notochord flex at $45^{\circ}$. Rudimental second dorsal, anal, caudal and ventral fins are also formed. The larvae attained 10.40~10.80 mm in TL, 35 days after hatching, are found to start the bottom-life after having completely formed first dorsal and ventral fins. The larvae reached the juvenile stage at 50~60 days after hatching and attained 15.37~20.25 mm in TL. At this period all scales appeared on the body.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.191-197
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• 2014

Purpose : This study presents the usefulness assessment of metal artifact reduction for orthopedic implants(O-MAR) to decrease metal artifacts from materials with high density when acquired CT images. Materials and Methods : By CT simulator, original CT images were acquired from Gammex and Rando phantom and those phantoms inserted with high density materials were scanned for other CT images with metal artifacts and then O-MAR was applied to those images, respectively. To evaluate CT images using Gammex phantom, 5 regions of interest(ROIs) were placed at 5 organs and 3 ROIs were set up at points affected by artifacts. The averages of standard deviation(SD) and CT numbers were compared with a plan using original image. For assessment of variations in dose of tissue around materials with high density, the volume of a cylindrical shape was designed at 3 places in images acquired from Rando phantom by Eclipse. With 6 MV, 7-fields, $15{\time}15cm2$ and 100 cGy per fraction, treatment planning was created and the mean dose were compared with a plan using original image. Results : In the test with the Gammex phantom, CT numbers had a few difference at established points and especially 3 points affected by artifacts had most of the same figures. In the case of O-MAR image, the more reduction in SD appeared at all of 8 points than non O-MAR image. In the test using the Rando Phantom, the variations in dose of tissue around high density materials had a few difference between original CT image and CT image with O-MAR. Conclusion : The CT images using O-MAR were acquired clearly at the boundary of tissue around high density materials and applying O-MAR was useful for correcting CT numbers.

• Progress in Medical Physics
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• v.25 no.3
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• pp.167-175
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• 2014

The purpose of this study is to evaluate the variation of the dose which is delivered to the patients with glottis cancer under IMRT (intensity modulated radiation therapy) by using the 3D registration with CBCT (cone beam CT) images and the DIR (deformable image registration) techniques. The CBCT images which were obtained at a one-week interval were reconstructed by using B-spline algorithm in DIR system, and doses were recalculated based on the newly obtained CBCT images. The dose distributions to the tumor and the critical organs were compared with reference. For the change of volume depending on weight at 3 to 5 weeks, there was increased of 1.38~2.04 kg on average. For the body surface depending on weight, there was decreased of 2.1 mm. The dose with transmitted to the carotid since three weeks was increased compared be more than 8.76% planned, and the thyroid gland was decreased to 26.4%. For the physical evaluation factors of the tumor, PITV, TCI, rDHI, mDHI, and CN were decreased to 4.32%, 5.78%, 44.54%, 12.32%, and 7.11%, respectively. Moreover, $D_{max}$, $D_{mean}$, $V_{67.50}$, and $D_{95}$ for PTV were increased or decreased to 2.99%, 1.52%, 5.78%, and 11.94%, respectively. Although there was no change of volume depending on weight, the change of body types occurred, and IMRT with the narrow composure margin sensitively responded to such a changing. For the glottis IMRT, the patient's weight changes should be observed and recorded to evaluate the actual dose distribution by using the DIR techniques, and more the adaptive treatment planning during the treatment course is needed to deliver the accurate dose to the patients.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.614-618
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• 2010

Background: The aim of our study was to assess the extent of regression of left ventricular mass after aortic valve replacement in isolated aortic regurgitation. Material and Method: Retrospective analysis of echocardiographic data was collected preoperative and postoperative 1 year. There were 20 patients (12 males, 8 females, mean age $55.8{\pm}11.8$ years, mean body surface area $1.64{\pm}0.19m^2$) with aortic regurgitation from 2002 through 2007. We studied the change of left ventricular ejection fraction, ventricular septum and left ventricular posterior wall thickness, and left vemtricular muscle index (LVMI). The control group was age matched with normal echocardiographic study results. Patients with combined surgery or infective endocarditis were excluded. Result: Seven cases of tissue valves and thirteen cases of mechanical valve were used. The valve sizes were 21 mm (3 cases), 23 mm (13 cases) and 25 mm (4 cases). The postoperative ($125.5{\pm}42g/m^2$) LVMI has decreased than preoperative LVMI ($212.3{\pm}80g/m^2$, p=0.000) but higher than that of control group ($80.5{\pm}15.9g/m^2$, p=0.000). Postoperative septal wall (systolic/diastolic: $13.5{\pm}3.4mm/17.1{\pm}4.1mm$) and left ventricular posterior wall (systolic/diastolic: $12.9{\pm}3.4mm/16.7{\pm}3.4mm$) thickness were slightly decreased after the valve replacement but was not significantly different than preoperative levels. And postoperative interventricular septal wall and left ventricular posterior wall thickness (systolic/diastolic: $8.6{\pm}1.4mm/12.1{\pm}1.7mm$, systolic/diastolic: $8.4{\pm}1.4mm/13.2{\pm}1.9mm$) were higher than that of the control group (p<0.001). Conclusion: The significant regression of LVMI after aortic valve replacement developed at postoperative one year but the level was higher than control group. The main cause of decreased LVMI is decreased in left ventricular dimension.

• Progress in Medical Physics
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• v.10 no.2
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• pp.63-71
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• 1999

For the purpose of utilization in 3-D conformal radiotherapy and whole body radiosurgery, the Whole Body 3-Dimensional Topographic Radiation Therapy System has been developed. Whole body frame was constructed in order to be installed on the couch. Radiopaque catheters were engraved on it for the dedicated coordinate system and a MeV-Green immobilizer was used for the patient setup by the help of side panels and plastic rods. By designing and constructing the whole body frame in this way, geometrical limitation to the gantry rotation in 3-D conformal radiotherapy could be minimized and problem which radiation transmission may be altered in particular incident angles was solved. By analyzing CT images containing information of patient setup with respect to the whole body frame, localization and coordination of the target is performed so that patient setup error may be eliminated between simulation and treatment. For the verification of setup, the change of patient positioning is detected and adjusted in order to minimize the setup error by means of comparison of the body outlines using 3 CCTV cameras. To enhance efficiency of treatment procedure, this work can be done in real time by watching the change of patient setup through the monitor. The method of image subtraction in IDL (Interactive Data Language) was used to visualize the change of patient setup. Rotating X-ray system was constructed for detecting target movement due to internal organ motion. Landmark screws were implanted either on the bones around target or inside target, and variation of target location with respect to markers may be visualized in order to minimize internal setup error through the anterior and the lateral image information taken from rotating X-ray system. For CT simulation, simulation software was developed using IDL on GUI(Graphic User Interface) basis for PC and includes functions of graphic handling, editing and data acquisition of images of internal organs as well as target for the preparation of treatment planning.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.1
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• pp.33-39
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• 2006

Purpose: To determine appropriate sampling frequency and time of multiple blood sampling dual exponential method with $^{99m}Tc$-DTPA for calculating glomerular filtration rate (GFR). Materials & Methods: Thirty four patients were included in this study. Three mCi of $^{99m}Tc$-DTPA was intravenously injected and blood sampling at 9 different times, 5ml each, were done. Using the radioactivity of serum, measured by gamma counter, the GFR was calculated using dual exponential method and corrected with the body surface area. Using spontaneously chosen 2 data points of serum radioactivity, 15 collections of 2-sample GFR were calculated. And 10 collections of 3-sample GFR and 12 collections of 4-sample GFR were also calculated. Using the 9-sample GFR as a reference value, degree of agreement was analyzed with Kendall's $\tau$ correlation coefficients, mean difference and standard deviation. Results: Although some of the 2-sample GFR showed high correlation coefficient, over or underestimation had evolved as the renal function change. The 10-120-240 min 3-sample GFR showed a high correlation coefficient (${\tau}=0.93$), minimal difference ($Mean{\pm}SD=-1.784{\pm}3.972$), and no over or underestimation as the renal function changed. The 4-sample GFR showed no better accuracy than the 3-sample GFR. Conclusions: In the wide spectrum of renal function, the 10-120-240 min 3-sample GFC could be the best choice for estimating the patients' renal function.

• Journal of fish pathology
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• v.10 no.2
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• pp.97-111
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• 1997

In the winter of 1995, mass mortality occurred in cultured flounder, Paralichthys olivaceus in Gurongpo, Kyoungbuk, Korea. From the observations of moribund and dead fish, parasitic ciliates, which were shown as white spots to the naked eye, were considered to be involved in the mass mortality. From heavily infected flounders, histopathological, morphological and biological characterization of these ciliates were carried out. In the histological observation, many ciliates were found under the epithelia of gill filaments and skin, and caused hyperplasia of epithelial and mucus cells at the infected areas. The ciliates found on the body surface, fins and gills were very similar to Cryptocaryon irritans. However the ciliates showed two different patterns of reproductian, i.e., typical form(palintomy)and atypical form(budding plus multiple fission) at $16^{\circ}C$ of water temperature. The occurrence ratio between typical and atypical form was about 3:2. Tomitogenesis takes 8-14 days in the typical and 13-15 days in the atypical form. In the viability test at different temperatures and salinities, the typical form died below 30‰ at $12^{\circ}C$, below 20‰ at $16^{\circ}C$, below 15‰ at $20^{\circ}C$, and below 25‰ at $24^{\circ}C$, respectively. On the other hand, the atypical form died below 20‰ at $12^{\circ}C$, below 15‰ at 16-$20^{\circ}C$, and below 25‰ at $24^{\circ}C$, respectively. The results suggested that the atypical has better viability at low salinity than that of the typical at low temperatures. In the excystment time and success rates of excystment according to temperatures, the typical form showed 8 days, 30% at $12^{\circ}C$ : 6.5 days, 50%, at $16^{\circ}C$ : 5.5 days, 75% at $20^{\circ}C$ : and 7 days, 10% at $24^{\circ}C$, respectively. On the other hand, the atypical form showed 15.5 days at $12^{\circ}C$ : 14 days, 76.6% at $16^{\circ}C$ : 12 days, 72.2% at $20^{\circ}C$ : 10 days 31.6% at $24^{\circ}C$, respectively. The results suggested that the atypical form had longer excystment time than that of the typical form at any temperature and showed better stability at low temperatures.

• Journal of fish pathology
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• v.23 no.1
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• pp.69-83
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• 2010

This study was aimed to investigate the effects of injection of garlic, Allium sativum, extract and immersion in garlic juice on the nonspecific immunity and the resistance against the artificial infection of Streptococcus iniae and Edwardsiella tarda of the olive flounder, Paralichthys olivaceus. The nonspecific immune mechanisms were assessed in terms of lysozyme activity, nitroblue-tetrazolium (NBT) assay and superoxide dismutase (SOD) activity etc. Relative percent survival (RPS) was assessed by the challenge with S. iniae BS10 or E. tarda KE-1. Almost of the garlic extract injected groups showed the enhanced level of the tested nonspecific immune factors. In the challenge test with S. iniae and E. tarda, RPS of 5% garlic extract pre-injected group was much higher than that of any other tested groups, respectively. Almost of the garlic juice immersion tested groups exhibited strengthened nonspecific immune defence factors, lysozyme activity, the number of lymphocytes and neutrophils, NBT reduction and SOD activity in kidney. In the challenge with S. iniae and E. tarda, RPS in the 0.25 g/L of garlic juice immersed group was much higher than any other tested groups, respectively. The results suggest that the garlic extract and juice would be effective to enhance the nonspecific immunity and protective ability of olive flounder against fish disease such as S. iniae and E. tarda.