• Proceedings of the Korean Vacuum Society Conference
• /
• 1998.02a
• /
• pp.133-133
• /
• 1998

In the thin film alloy formation of the transition metals ion-beam-mixing technique forms a metastable structure which cannot be found in the arc-melted metal alloys. Sppecifically it is well known that the studies about the electronic structure of ion-beam-mixed alloys pprovide the useful information in understanding the metastable structures in the metal alloy. We studied the electronic change in the ion-beam-mixed ppt-Ct alloys by XppS and XANES. These analysis tools pprovide us information about the charge transfer in the valence band of intermetallic bonding. The multi-layered films were depposited on the SiO2 substrate by the sequential electron beam evapporation at a ppressure of less than 5$\times$10-7 Torr. These compprise of 4 ppairs of ppt and Cu layers where thicknesses of each layer were varied in order to change the alloy compposition. Ion-beam-mixing pprocess was carried out with 80 keV Ae+ ions with a dose of $1.5\times$ 1016 Ar+/cm2 at room tempperature. The core and valence level energy shift in these system were investigated by x-ray pphotoelectron sppectroscoppy(XppS) pphotoelectrons were excited by monochromatized Al K ａ(1486.6 eV) The ppass energy of the hemisppherical analyzer was 23.5 eV. Core-level binding energies were calibrated with the Fermi level edge. ppt L3-edge and Cu K-edge XANES sppectra were measured with the flourescence mode detector at the 3C1 beam line of the ppLS (ppohang light source). By using the change of White line(WL) area of the each metal sites and the core level shift we can obtain the information about the electrons pparticippating in the intermetallic bonding of the ion-beam-mixed alloys.

• Journal of Veterinary Clinics
• /
• v.37 no.2
• /
• pp.82-87
• /
• 2020

The purpose of this study is to evaluate the azygos vein to aorta diameter ratio (AV/AO ratio) in healthy dogs and dogs with diseases that may cause azygos vein dilation. The normal groups included eleven healthy beagle dogs and eleven small breed dogs. The abnormal group included 43 dogs that had diseases with high right atrial pressure (RA group), obstruction of cranial or caudal vena cava (CVC group) and porto-azygos shunt group (PSS group). The diameter of AV and AO were measured at three sites on thoracic CT images; the level of the cranial endplate of 12^th thoracic vertebra (TV level), the tracheal bifurcation (TB level) and the insertion to the cranial vena cava (CrVC level). The AV/AO ratio at the CrVC level had significantly higher values than those at the TV and TB levels in the normal groups. The AV/AO ratios of TV and TB levels in the CVC group and the values at all measurement sites of the PSS group were significantly higher than the normal groups. AV/AO ratio will be a useful factor for the evaluation of various clinical conditions that change the AV diameter with respect independent to the body weight in dogs.

• Journal of the Korean Society of Radiology
• /
• v.83 no.4
• /
• pp.846-860
• /
• 2022

Persistent left superior vena cava (PLSVC) is a rare congenital, thoracic, and vascular anomaly. Although PLSVCs generally do not have a hemodynamic effect, several types of PLSVC and some cardiac anomalies may manifest with clinical symptoms. The presence of PLSVC can render catheterization via left subclavian access difficult when placing a pacemaker or central venous catheter. As such, recognizing a PLSVC that is typically incidentally discovered can prevent complications such as vascular injury. Differentiating vessels found in a similar location as PLSVC is necessary when performing thoracic vascular procedures. This pictorial essay explains the multi-detector CT findings of a PLSVC, and provides a summary of other blood vessels that require differentiation during thoracic vascular procedures.

• Journal of the Korea Convergence Society
• /
• v.7 no.1
• /
• pp.89-95
• /
• 2016

The purpose of this experiment intend to evaluate the quality of the image based on the orbit and basal ganglia with high radiosensitivity for the noise, SNR and dose using the five kinds patient fixing pad in brain phantom MDCT(BrillianceTM CT 64 slice, PHILIPS, Netherward). The noise had a higher values in AP than those of others, but the SNR was lower in AP than those of others. The SNR was higher in UP than those of RP, PP, SP and AP. The UP, RP and PP were no statistically significant(p>0.05), whereas it was significant difference between UP, RP, PP and SP, AP(p<0.05). This is causes of the noise difference is generated due to the differences in the radiation absorption dose in accordance with each the component of the absorbed dose level of the detector according to the reference line and each of SOML when the radiation exposured. The CTDIvol(mGy) and DLP of orbit and basal ganglia were 56.95, 911.50, respectively. There is no difference between both mean dose. In conclusion, it is possible to distinguish among a kind of 5 patient fixing pad by using brain phantom MDCT. Overall, patient fixing pad of UP, RP and PP based on a brain phantom MDCT can provide useful information.

• Progress in Medical Physics
• /
• v.18 no.3
• /
• pp.139-143
• /
• 2007

The purpose of this study was to measure and evaluate radiation dose for MDCT parameters. Patient dose for various combination of MDCT parameters were experimentally measured, using MDCT (GE light speed plus 4 slice, USA), model 2026C electrometer (RADICAL 2026C, USA), standard Polymethylmethacrylate (PMMA) head and body CT dosimetry phantoms. In clinical situations, for a typical abdominal scan performed with MDCT at 120 kVp, 180 mAs, 20 mm collimation, and a pitch of 0.75 $CTDI_w,\;CTDI_{vol}$ were measured as 20.2 mGy, 26.9 mGy, respectively. When scan length is assumed as 271.3 mm, DLP and measured effective dose of the abdominal would be calculated as $729.1\;mGy{\cdot}cm$, 10.9 mSv, respectively.

• Imaging Science in Dentistry
• /
• v.46 no.1
• /
• pp.25-31
• /
• 2016

Purpose: This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes. Materials and Methods: Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using 3D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex. Results: The mean of the average point-to-point distances on condylar surface was $0.11{\pm}0.03mm$. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females. Conclusion: This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.

• Archives of Plastic Surgery
• /
• v.37 no.5
• /
• pp.577-582
• /
• 2010

Purpose: When reconstruction for patients who have the large contralateral breast or a following large defect after mastectomy is required, conventional pedicled TRAM flap shows the unpredictable occurrence of fat necrosis and skin flap loss in a relatively high percentage due to insufficient blood supply. In an effort to obtain more stable TRAM flap blood circulation, we have performed a supercharged technique using deep inferior epigastric perforators (DIEP) with conventional pedicled TRAM flap. Methods: From September of 2006 to December of 2008, Fourteen supercharged TRAM flap were performed for breast reconstruction after modified radical mastectomy. The contralateral DIEP was anastomosed to the internal mammary vessels in contralateral pedicled TRAM flap or thoracodorsal vessels in ipsilateral pedicled TRAM flap. Nutrient vessels were selected by Multi-Detector Computed tomography (MD-CT) modalities. For the nutrient vessel, we used deep inferior epigastric vessels (DIEV) of the ipsilateral side in 8 patients, DIEV of the contralateral side in 6 patients. In addition, for the recipient vessel, we used thoracodorsal vessels in 8 patients, internal mammary vessels in 5 patients, intercostals artery perforators in 1 patient. Results: The mean age was 46.8 years and the average follow-up interval was 14 months. There were 11 immediate and 3 delayed breast reconstructions. Fat necrosis incidence rate in supercharged TRAM group was lower than in conventional TRAM flap group. There were no differences of the incidences of abdominal hernia in both groups. Conclusion: The supercharged TRAM flap produces an improvement in vascularity that permits use of all four zones of the flap. The breast reconstruction with supercharged technique is reliable and valuable methods which provide sufficient soft tissue from abdomen without significant complications.

• Clinical and Experimental Pediatrics
• /
• v.48 no.8
• /
• pp.901-906
• /
• 2005

Kawasaki disease (KD) is a leading cause of acquired heart disease in children. Yet the etiology of KD is still unknown and diagnosis depends on the exclusion of other diseases and the clinical manifestations meeting the defined criteria. Young infants frequently show atypical clinical courses and are frequently complicated with coronary aneurysms. Some cases show thrombocytopenia, which is known as one of the risk factors for complications with coronary aneurysms. So, a high index of suspicion is the most important factor for the diagnosis of KD in very young infants or adolescents whose clinical courses are equivocal. We report herein on a case of KD in an 80-day-old female infant with fever and seizure with bloody stool; laboratory findings were those of sepsis with disseminated intravascular coagulopathy. In spite of aggressive treatments, fever and thrombocytopenia persisted for two weeks and huge coronary aneurysms developed at the third week in all three major coronary arteries; the diameter of the right one was as large as the aortic annulus. Three months later, huge pulsatile masses developed in both axillas; these were found to be huge axillary aneurysms defined very clearly on multi-detector CT scan. She has been under follow up with antiplatelets and anticoagulation therapy with poor regression of the aneurysms.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.41
• /
• pp.33.1-33.7
• /
• 2019

Background: The concept of the ideal morphology for the alveolar bone form is an important element to reconstruct or restore the in maximizing esthetic profile and functional alveolar bone restoration. The purpose of this preliminary study is to evaluate the normal alveolar bone structure to provide the standard reference and guide template for use in diagnosing for implant placement, determining the correct amount of bone augmentation in actual clinical practice and producing prostheses based on three-dimensional imaging assessment of alveolar bone. Methods: This study was included 11 men and 11 women (average age, 22.6 and 24.5 years, respectively) selected from among 127 patients. The horizontal widths of alveolar bone of maxilla and mandible were measured at the crestal, mid-root, and root apex level on MDCT (multi-detector computed tomography) images reconstructed by medical imaging software. In addition, tooth dimensions of the central incisors, canines, second premolars, and first molars of maxilla and mandible, including the horizontal width of the interdental alveolar bone crest, were also measured and statistically analyzed. Results: The horizontal alveolar bone width of the palatal side of maxilla showed a distinct increment from the alveolar bone crest to the apical region in both anterior and posterior areas. The average widths of the maxillary alveolar ridge were as follows: central incisor, 7.43 mm; canine, 8.91 mm; second premolar, 9.57 mm; and first molar, 12.38 mm. The average widths of the mandibular alveolar ridge were as follows: central incisor, 6.21 mm; canine, 8.55 mm; second premolar, 8.45 mm; and first molar, 10.02 mm. In the buccal side, the alveolar bone width was not increased from the crest to the apical region. The horizontal alveolar bone width of an apical and mandibular border region was thinner than at the mid-root level. Conclusions: The results of the preliminary study are useful as a clinical guideline when determining dental implant diameter and position. And also, these measurements can also be useful during the production of prefabricated membranes and customized alveolar bone scaffolds.

• The Journal of Korean Society for Radiation Therapy
• /
• v.26 no.1
• /
• pp.137-147
• /
• 2014

Purpose : The purpose of this study is to verify the accuracy of dose delivery according to the patient's breathing cycle in Gated Volumetric Modulated Arc Therapy Materials and Methods : TrueBeam STxTM(Varian Medical System, Palo Alto, CA) was used in this experiment. The Computed tomography(CT) images that were acquired with RANDO Phantom(Alderson Research Laboratories Inc. Stamford. CT, USA), using Computerized treatment planning system(Eclipse 10.0, Varian, USA), were used to create VMAT plans using 10MV FFF with 1500 cGy/fx (case 1, 2, 3) and 220 cGy/fx(case 4, 5, 6) of doserate of 1200 MU/min. The regular respiratory period of 1.5, 2.5, 3.5 and 4.5 sec and the patients respiratory period of 2.2 and 3.5 sec were reproduced with the $QUASAR^{TM}$ Respiratory Motion Phantom(Modus Medical Devices Inc), and it was set up to deliver radiation at the phase mode between the ranges of 30 to 70%. The results were measured at respective respiratory conditions by a 2-Dimensional ion chamber array detector(I'mRT Matrixx, IBA Dosimetry, Germany) and a MultiCube Phantom(IBA Dosimetry, Germany), and the Gamma pass rate(3 mm, 3%) were compared by the IMRT analysis program(OmniPro I'mRT system software Version 1.7b, IBA Dosimetry, Germany) Results : The gamma pass rates of Case 1, 2, 3, 4, 5 and 6 were the results of 100.0, 97.6, 98.1, 96.3, 93.0, 94.8% at a regular respiratory period of 1.5 sec and 98.8, 99.5, 97.5, 99.5, 98.3, 99.6% at 2.5 sec, 99.6, 96.6, 97.5, 99.2, 97.8, 99.1% at 3.5 sec and 99.4, 96.3, 97.2, 99.0, 98.0, 99.3% at 4.5 sec, respectively. When a patient's respiration was reproduced, 97.7, 95.4, 96.2, 98.9, 96.2, 98.4% at average respiratory period of 2.2 sec, and 97.3, 97.5, 96.8, 100.0, 99.3, 99.8% at 3.5 sec, respectively. Conclusion : The experiment showed clinically reliable results of a Gamma pass rate of 95% or more when 2.5 sec or more of a regular breathing period and the patient's breathing were reproduced. While it showed the results of 93.0% and 94.8% at a regular breathing period of 1.5 sec of Case 5 and 6, it could be confirmed that the accurate dose delivery could be possible on the most respiratory conditions because based on the results of 100 patients's respiratory period analysis as no one sustained a respiration of 1.5 sec. But, pretreatment dose verification should be precede because we can't exclude the possibility of error occurrence due to extremely short respiratory period, also a training at the simulation and careful monitoring are necessary for a patient to maintain stable breathing. Consequently, more reliable and accurate treatments can be administered.