• The Journal of Korean Society for Radiation Therapy
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• v.19 no.2
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• pp.123-129
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• 2007

Purpose: CT scan shows that significant tumor movement occurs in lesions located in the proximity of the heart, diaphragm, and lung hilus. There are differences concerning three kinds of type to get images following the Scan type called Axial, Helical, Cine (4D-CT) mode, when the scanning by CT. To know how each protocol describe accurately, this paper is going to give you reappearance using the moving phantom. Materials and Methods: To reconstruct the movement of superior-inferior and anterior-posterior, the manufactured moving phantom and the motor following breathing were used. To distinguish movement from captured images by CT scanning, a localizer adhered to the marker on the motor. The moving phantom fixed the movement of superior-inferior upon 1.3 cm /1 min. The motor following breathing fixed the movement of anterior-posterior upon 0.2 cm /1 min. After fixing each movement, CT scanning was taken by following the CT protocols. The movement of A localizer and volume-reappearance analyzed by RTP machine. Results: Total volume of a marker was 88.2 $cm^3$ considering movement of superior-inferior. Total volume was 184.3 $cm^3$. Total volume according to each CT scan protocol were 135 $cm^3$ by axial mode, 164.9 $cm^3$ by helical mode, 181.7 $cm^3$ by cine (4D-CT) mode. The most closely describable protocol about moving reappearance was cine mode, the marker attached localizer as well. Conclusion: CT scan should reappear concerning a exact organ-description and target, when the moving organ is being scanned by three kinds of CT protocols. The cine (4D-CT) mode has the advantage of the most highly reconstructible ability of the three protocols in reappearance of the marker using a moving phantom. The marker on the phantom has always regular motion but breathing patients don't move like a phantom. Breathing education and devices setting patients were needed so that images reconstruct breathing as exactly as possible. Users should also consider that an amount of radiation to patients is being bombed.

• Korean Journal of Veterinary Research
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• v.9 no.1
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• pp.1-9
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• 1969

The experimental studies were performed to observe the characteristics of the myelinated nerve fibers of the tradiaphragmatic branches of phrenic nerves in dog In the work to be reported five mixed breed Korean dog were used, they were one year old and he body eights were about 12 Kgm. in average with healthy conditions. The specimens (nerve) were taken at the point of 1.5 cm posterior part from the left and right phrenic nerves entrance to the diaphragm, and the dorso-lateral and dorso-medial branches of phrenic nerves vere also, taken at the point of 0.5 cm distal part from their branching portion. The specimens were fixed for 24 hrs. in Flemming's solution, and embedded in paraffin. The paraffin section. were cut at 6 microns and stained with Walter's modification of Weigert-pal method for the myelinated fibers. Microphotographs were taken and enlarged into 750 times of the actual size, and the diameter of the photographic images of the myelinated fibers were measured by the scale on the transparent Percepex Plate. The following conclusions were made: 1. The percentage of distribution of the several intradiaphragmatic branches of phrenic nerves were as follows. Ventral branches were 34.97%, lateral branches were 37.90%, dorsal branches were 27.13%, and the dorsal branches were branched again into dorso-lateral branches(54.22%) and dorso-medial branches (45. 78%). 2. The mean value and S.D. of the total numbers of the myelinated nerve fibers at the left ventral branches were $490.80{\pm}12$, and at the right ventral branches were $486.6{\pm}13$. Total average cross sectional area on the left ventral branches were 38,000. $6{\pm}136{\mu}^2$, and the right ventral branches were $37,150.2{\pm}1.782{\mu}^2$. 3. The mean value and S.D. of the total numbers of the myelinated nerve fibers at the left lateral branches were $533.8{\pm}8$, and at the right lateral branches were $525.6{\pm}7$. Total average cross sectional area of the left lateral branches were $41,582{\pm}1,170{\mu}^2$, and the right lateral branches were $40,454.8{\pm}812{\mu}^2$. 4. The mean value and S.D. of the total numbers of the myelinated nerve fibers at the left dorsal branches were $378.2{\pm}14$, and at the right dorsal branches were $380.2{\pm}8$. Total average cross sectional area of the left dorsal branches were $27,771{\pm}1,256{\mu}^2$, and the right dorsal branches were $27,507.2{\pm}645{\mu}^2$. 5. The mean value and S.D. of the total numbers of the myelinated fibers at the left dorso-lateral branches were $205.4{\pm}15$, and at the right dorso-lateral branches were $210.6{\pm}17$. Total average cross sectional area of the left dorso lateral branches were $15,354. 8{\pm}1,519{\mu}^2$, and the right dorsal branches were $15,887{\pm}1,297{\mu}^2$. 6. The mean value and S.D. of the total numbers of the myelinated nerve fibers at the left dorso-medial branches were $175{\pm}14$, and at the right dorso-medial branches were $176.2{\pm}17$. Total average cross sectional area of the left dorso-medial branches were $13,037.4{\pm}944{\mu}^2$, and at the right dorso-medial branches were, $13,103{\pm}1,373{\mu}^2$. 7. The highest frequent distribution of the intradiaphragmatic branches of phrenic nerves were found in the $10-12{\mu}^2$ groups, and they were almost 30% of the total groups. 8. The largest fibers diameter were in the $14-16{\mu}^2$ groups, and these were shown the lowest frequent distribution. 9. The largest cross sectional area of the intradiaphragmatic branches of phrenic nerves were found in the $10-12{\mu}^2$ groups. 10. All of the intradiaphragmatic branches of phrenic nerves were unimodal which has a peak in the $10-12{\mu}^2$ groups.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3A
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• pp.235-249
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• 2011

A new form of I-type PSC bridge girder, which has hole in the web, is proposed in this paper. Three different concepts were combined and implemented in the design. First of all, a girder was precast at a manufacturing plant as divided pieces and assembled at the construction site using post-tensioning method, and the construction period at the site will be reduced dramatically. In this way, the quality of concrete can be assured at the manufacturing factory and concrete curing can be well controlled, and the spliced girder segments can be moved to the construction site without a transportation problem. Secondly, a numerous number of holes was made in the web of the girder. This reduces the self-weight of the girder. But more important thing related to the holes is that about half of the total anchorages can be moved from the girder ends into individual holes. The magnitude of negative moment developed at girder ends will be reduced. Also, since the longitudinal compressive stresses are reduced at ends, thick end diaphragm is not necessary. Thirdly, Prestressing force was introduced into the member through multiple stages. This concept of multi-stage prestressing method overcomes the prestressing force limit restrained by the allowable stresses at each loading stage, and maximizes the magnitude of applicable prestressing force. It makes the girder longer and shallower. Two 50 meter long full scale girders were fabricated and tested. One of them was non-spliced, or monolithic girder, made as one piece from the beginning, and the other one was assembled using post-tensioning method from five pieces of segments. It was found from the result that monolithic and spliced girder show similar load-deflection relationships and crack patterns. Girders satisfied specific girder design specification in flexural strength, deflection, and live load deflection control limit. Both spliced and monolithic holed web post-tensioned girders can be used to achieve span lengths of more than 50m with the girder height of 2 m.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.7-10
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• 2013

Purpose : This study evaluated the effects of breathing protocols on matching results of PET and CT images using two breathing protocols such as free breathing and acquisition in holding the breathing after the normal expiration in acquiring CT images. Materials and Methods: Whole body FDG PET and CT images of 200 patients (mean age: 58 (range 20~84), 103 males and 97 females) using Discovery VCT (GE Healthcare, Milwaukee, USA). When taking CT images, subjects were asked to breathe freely (free breathing, n=100) or hold the breathing after the normal expiration (Hold, n=100). In the whole body image coronal section where PET and CT were matched, the matched error of the boundary between diaphragm and liver was measured in length. The matched errors were compared according to breathing protocol by age, sex and disease. The verification of statistical significance was made by SPSS 15.0 (SPSS Inc., Chicago, IL, USA) via one way ANOVA. Results: The matched error in all was 0.87 mm. According to breathing protocol, there was no significant difference in matched error as1.01 mm in free breathing and as 0.73 mm in hold breathing (p=.688). The matched error according to sex did not show significant difference as 1.08 mm of males, and 0.93 mm of females in free breathing (p=.517). In hold breathing, there was no significant difference as 0.79 mm of males and 0.66 mm of females (p=.738). There was no significant difference in matched error by age between free breathing and hold breathing (free breathing (p=.728), hold (p=.465). There was no significant difference in matched error by disease between free breathing and hold breathing (free breathing (p=.197), hold (p=.518) Conclusion: The difference in matched error between free breathing and hold breathing was less than 5 mm at 99%. There was no statistically significant difference in matched error by breathing protocol, age and disease. It was proved that there was no difference in matched error between PET and CT images according to breathing protocol during PET/CT scan.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.3-7
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• 2010

Purpose: The usefulness of Positron Emission Tomography (PET) images in diagnosis, staging, recurrent and treatment response evaluation has already been known. However, tumors which are small size, located in lower lobe of lung or upper lobe of liver are shown misalignment, distortion and different Standard Uptake Value (SUV) by respiration in PET images. Therefore, if radiotherapy based on normal respiration, it may cause low treatment response or more side effects because targets which had to treat, out of treat range or over dose to normal tissue. The purpose of this study is to evaluate attenuation-correction with Average CT (ACT) for more accuracy SUV measurement and minimize artifact by respiration. Materials and Methods: 13 patients, who had tumors which are around the diaphragm, underwent ACT scan after Helical CT (HCT) scan with PET/CT (Discovery DSTE 8; GE Healthcare). We quantified the differences between attenuation corrected image with HCT and attenuation corrected image with ACT in artifact size and maximum SUV ($SUV_{max}$). Artifacts were evaluated by measurement of the curved photogenic area in the lower thorax of the PET images for all patients. $SUV_{max}$ was measured separately at the primary tumors. Analysis program was Advantage Workstation v4.3 (GE Healthcare). Patients were injected with 7.4 MBq (0.2 $mC_i$) per kg of $^{18}F$-FDG and scanned 1 hour after injection. The PET acquisition was 3 minute per bed. Results: Significantly lower artifact were observed in PET/ACT images than in PET/HCT images (below-thoracic artifacts caused by under corrected $1.5{\pm}3.5$ cm vs. $13.4{\pm}4.2$ cm). Significantly higher $SUV_{max}$ were noted in PET/ACT images than in PET/HCT images in the primary tumor. Compared with PET/HCT images, $SUV_{max}$ in PET/ACT images were higher by $5.3{\pm}3.9%$ (mean value) tumor. The highest difference was observed in Lower lobe of lung (7.7 to 8.7; 13%). Conclusion: Due to its significantly reduced artifacts in lower thoracic, attenuation corrected image with ACT images provided more reliable $SUV_{max}$ and may be helpful in monitoring treatment response. Moreover, ACT can separate upper lobe of liver and lower lobe of lung, it may be helpful in interpretation. ACT will be clinically useful, considering increased dose caused by ACT scan and adapt.

• Tuberculosis and Respiratory Diseases
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• v.66 no.4
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• pp.288-294
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• 2009

Background: A lung hyperinflation, or air trapping, caused by expiratory flow-limitation contributes to dyspnea in patients with chronic obstructive pulmonary disease (COPD). Forced expiratory volume in 1 second ($FEV_1$) has served as an important diagnostic measurement of COPD, but does not correlate with patient-centered outcomes such as dyspnea. Therefore, this study was performed to investigate the role of radiologic quantity in evaluating the dyspnea in patients with COPD by measuring lung hyperinflation in chest x-ray and high resolution chest tomography (HRCT). Methods: Fifty patients with COPD were enrolled in this study. Their subjective dyspnea score (modified Borg scale dyspnea index), spirometry, and lung volume were measured. Simultaneous hyperinflations of chest x-ray score ("chest score") and degree of emphysema of HRCT ("HRCT score") were measured. The "chest score" were composed of lung length, retrosternal space width, and height of the arc of the diaphragm and "HRCT score" were composed of severity and extent of emphysema. Results: The mean age of patients was 69 years old and their mean $FEV_1$ was 51.7%. The Borg score significantly correlated with parameters of spirometry and lung volume, including FVC, $FEV_1$, $FEV_1$/FVC, RV, RV/TLC, and DLCO. The Borg score correlated well with "HRCT score", but did not correlate with "chest score". Also, the Borg scale correlates inversely with body mass index. Conclusion: The quantity of emphysema on chest HRCT may serve as an objective marker of dyspnea in patients with COPD.

• Journal of Veterinary Clinics
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• v.27 no.3
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• pp.273-283
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• 2010

The objective of this study was to measure densities in various areas of the normal canine lung with computed tomography (CT) depending on influences of gravity and the degree of lung inflation and to determine optimal positions and positive end expiratory pressure of canine lung for CT scanning. In each eight normal Beagle and Shihtzu dogs, a respiratory breathhold maneuver without spontaenous breathing at different positive end expiratory pressure (PEEP) of 0 mmHg, 10 mmHg and 20 mmHg was applied with the position of right and left lateral recumbency, sternal recumbency, and dorsal recumbency and spiral-CT scans of the total lung were acquired. Slices were selected at three levels through the apex, middle and basal lung at the aortic arch, carina and just above the diaphragm and lung density was measured in the dorsal, ventral, and lateral portions of the peripheral lung field. Lung density in dependent areas was higher than in nondependent areas (p < 0.05) regardless of species, positions, anatomic locations at the PEEP of 0 mmHg and 10 mmHg. However, no significant difference of lung density was found at PEEP of 20 mmHg in both species except the dorsal recumbency in Shihtzu dogs. This density gradient in the dependent areas is strongly influenced by PEEP (p < 0.05). In the four positions on the CT gantry, the lung density at the dependent and nondependent location of the lung was greater at the aortic arch than at the base (p < 0.05). Lung density decreased on identical location according to increase of PEEP (p < 0.05). There was no significant difference between right and left lung density at sternal and dorsal recumbency and no significant difference of the dorsal, ventral, and lateral portions of lung density at the right and left recumbency under identical pressure. It is implied that during chest CT scan with 20 mmHg of positive end expiratory pressure with right or left lateral recumbency, canine lung density do not influenced by gravity or anatomic location.

• Radiation Oncology Journal
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• v.23 no.4
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• pp.217-222
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• 2005

Purpose: To develop the respiration simulating phantom with thermocouple for evaluating 4D radiotherapy such as gated radiotherapy breathing control radiotherapy and dynamic tumor tracking radiotherapy. Materials and Methods: The respiration monitoring mask(ReMM) with thermocouple was developed to monitor the patient's irregular respiration. The signal from ReMM controls the simulating phantom as organ motion of patients in real-time. The organ and the phantom motion were compared with its respiratory curves to evaluate the simulating phantom. ReMM was used to measure patients' respiration, and the movement of simulating phantom was measured by using $RPM^{(R)}$. The fluoroscope was used to monitor the patient's diaphragm motion. relative to the organ motion, respectively. The standard deviation of discrepancy between the respiratory curve and the organ motion was 8.52% of motion range. Conclusion: Patients felt comfortable with ReMM. The relationship between the signal from ReMM and the organ motion shows strong correlation. The phantom simulates the organ motion in real-time according to the respiratory signal from the ReMM. It is expected that the simulating phantom with ReMM could be used to verify the 4D radiotherapy.

• The Korean Journal of Pain
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• v.2 no.2
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• pp.135-144
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• 1989

Celiac plexus block is recommended in patients with intractable upper abdominal cancer pain. The success rate of a celiac plexus block is variable among the authors. One of the causes of this is the anatomical variations of the celiac plexus. There has not been a study concerning anatomical observations of the celiac plexus in Korean cadavers. So, anatomical dissections were performed and observations were made of the celiac plexus and related structures in Korean cadavers. The results were as follows: 1) The subjects were 21 male bodies and 5 female bodies. The mean age at death was $69.9{\pm}15.5$ years (range 37~93). The mean height was $155.5{\pm}8.3\;cm$ (range 143~172). 2) The number of celiac ganglia ranged from 1~4. The mean numbers were $2.3{\pm}1.9$ in the right plexus and $1.9{\pm}0.8$ in the left, and the mean sizes were $18.9{\pm}7.7{\times}8.0{\pm}3.8\;mm^2$ and $18.5{\pm}8.3{\times}9.5{\pm}3.9\;mm^2$ respectively. 3) Celiac ganglia were most frequently located at the level of the upper third and middle third of L1 in both sides (65.5% in right, 64.0% in left). The vertical range of celiac ganglia ranged from 1 space, which is one third the height of one vertebral body, to 4 spaces. Mean vertical ranges were $1.5{\pm}0.6$ spaces in the right plexus and $1.6{\pm}0.7$ spaces in the left. The celiac ganglia located at the level of the upper third of L1 in the right and the lower third of L1 in the left side, had the largest vertical ranges respectively ($1.8{\pm}0.5$ spaces in right, $2.3{\pm}0.6$ spaces in left) 4) Right side celiac ganglia were located near the midline of the vertebrae compared to the left ones (mean 5.0 mm) The horizontal dimension was greater in the right ganglia ($24.2{\pm}9.2\;mm$) than in the left ganglia ($l8.8{\pm}7.0\;mm$). 5) There was no vertebral level difference between both celiac ganglia in most cases (60%). However, of the 40% of cases at different levels, in half of these (20%) the right ganglia were located higher than the left ganglia; and in the other 20%, this was reversed. 6) The origin sites of the celiac artery were most frequently in the upper third and middle third of L1 (61.6%). The celiac ganglia were usually located at the same level as the site of origin of the celiac artery (61.6% in right, 52.0% in left). 7) The vertebral level of the splanchnic nerves piercing the abdominal surface of the diaphragm was most frequently in the upper third and middle third of L1 (66.6% in right, 66.7% in left). 8) The level of the origin of diaphragmatic crura from the anterior surface of the vertebral bodies varied from the L1-L2 interspace to the L3-L4 interspace. Right crura most frequently originated at the level of the lower third of L2 to the upper third of L3 (57.6%), while left crura originated from the level of the L2-L3 interspace to the middle third of L3 (69.3%). From the above results, we realized that there were some anatomical variations of the celiac plexus and its relations to adjacent structures in Korean bodies. However, when the needle point is behind the anterior margin of the upper third of L1, it is possible to perform a successful retrocrural splanchnic nerve block.

• Journal of Sensor Science and Technology
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• v.7 no.3
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• pp.154-162
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• 1998

A planar Bi-Sb multijunction thermal converter with high thermal sensitivity and small ac-dc transfer error has been fabricated by preparing the bifilar thin film Pt-heater and the hot junctions of thin film Bi-Sb thermopile on the $Si_{3}N_{4}/SiO_{2}/Si_{3}N_{4}$-diaphragm, which functions as a thermal isolation layer, and the cold junctions on the dielectric membrane supported with the Si-substrate, which acts as a heat sink, and its ac-dc transfer characteristics were investigated with the fast reversed dc method. The respective thermal sensitivities of the converter with single bifilar heater were about 10.1 mV/mW and 14.8 mV/mW in the air and vacuum, and those of the converter with dual bifilar heater were about 5.1 mV/mW and 7.6 mV/mW, and about 5.3 mV/mW and 7.8 mV/mW in the air and vacuum for the inputs of inside and outside heaters, indicating that the thermal sensitivities in the vacuum, where there is rarely thermal loss caused by gas, are higher than those in the air. The ac-dc voltage and current transfer difference ranges of the converter with single bifilar heater were about ${\pm}1.80\;ppm$ and ${\pm}0.58\;ppm$, and those of the converter with dual bifilar heater were about ${\pm}0.63\;ppm$ and ${\pm}0.25\;ppm$, and about ${\pm}0.53\;ppm$ and ${\pm}0.27\;ppm$, respectively, for the inputs of inside and outside heaters, in the frequency range below 10 kHz and in the air.