• Title/Summary/Keyword: X-Rays

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Thermoluminescene Properties of Li6Gd(BO3)3:Ce3+ Scintillation Single Crystal (리튬 가돌리늄 보레이트 섬광단결정의 열형광 특성)

  • Kim, Sunghwan;Lee, Joonil
    • Journal of the Korean Society of Radiology
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    • v.8 no.7
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    • pp.455-459
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    • 2014
  • We grew the $Li_6Gd(BO_3)_3:Ce^{3+}$ scintillator and determined the scintillation and thermoluminescence properties for X-rays. The emission spectrum of $Li_6Gd(BO_3)_3:Ce^{3+}$ is located in the range of 370~500 nm, peaking at 423 nm an 455 nm, due to the $4f{\rightarrow}5d$ transition of $Ce^{3+}$ ions. The fluorescence decay time of the crystal is composed three components. The fast component is 60 ns (25%), the intermediate component is 787 ns (29%) and the slow component is $5.9{\mu}s$ (46%) of the crystal. The after-glow is caused by the electron and hole traps in the crystal lattice. We determined physical parameters of the traps in the crystal. The thermoluminescence trap are composed two traps. The determined activation energy (E), kinetic order (m) and frequency factor (s) of the first trap are 0.65 eV, 1.01 and $6.9{\times}10^8s^{-1}$. And, the determined activation energy, kinetic order and frequency factor of the second trap are 0.96 eV, 1.79 and $3.1{\times}10^{12 }s^{-1}$, respectively.

Reversible Data Hiding and Message Authentication for Medical Images (의료영상을 위한 복원 가능한 정보 은닉 및 메시지 인증)

  • Kim, Cheon-Shik;Yoon, Eun-Jun;Jo, Min-Ho;Hong, You-Sik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.1
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    • pp.65-72
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    • 2010
  • Nowadays, most hospitals have been used to create MRI or CT and managed them. Doctors depend on fast access to images such as magnetic resonance imaging (MRIs), computerized tomography (CT) scans, and X-rays for accurate diagnoses. Those image data are related privacy of a patient. Therefore, it should be protected from hackers and managed perfectly. In this paper, we propose a data hiding method into MRI or CT related a condition and intervention of a patient, and it is suggested that how to authenticate patient information from an image. In this way, we create hash code using HMAC with patient information, and hash code and patient information is hided into an image. After then, doctor will check authentication using HMAC. In addition, we use a reversible data hiding DE(Difference Expansion) algorithm to hide patient information. This technique is possible to reconstruct the original image with stego image. Therefore, doctor can easily be possible to check condition of a patient. As a consequence of an experiment with MRI image, data hiding, extraction and reconstruct is shown compact performance.

Transpatellar Cannulated Screw Fixation of Displaced Tibial Intercondylar Eminence Fractures (전위성 경골 과간 융기부 골절의 슬개골 하단을 통한 삽관 나사못 고정술)

  • Nha Koung Wook;Jung Byung Hyun;Suh Jin Soo;Suk Seung Yeub;Park Gyu Won;Chae Dong Ju
    • Journal of the Korean Arthroscopy Society
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    • v.6 no.1
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    • pp.25-30
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    • 2002
  • Purpose : To evaluate the clinical results of displaced tibial intercondylar eminence fractures which were treated with transpatellar cannulated screw fixation. Materials and Methods : Ten patients with displaced tibial intercondylar eminence fractures were treated between December 1998 and May 2001 and then followed up for more than one year. They were treated arthroscopic reduction and fixation of fracture site by cannulated screw through the hole of nonarticular surface of inferior patella. They were prospectively evaluated with regard to their clinical and radiologic results. Results : Radiologic unions occurred at an average of 9.2 weeks. Average anterior displacements were 1.8 mm in stress x-rays and 1.1 mm in KT-2000 arthrometer. Average loss of extension was $4.1^{\circ}$. Functional results were excellent in 7 cases and good in 3 cases. Conclusion : Arthroscopic transpatellar cannulated screw fixation is one of the useful methods for the treatment of displaced tibial intercondylar eminence fractures.

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A study of upper airway dimensional change according to maxillary superior movement after orthognathic surgery (양악 수술 시 상악골 상방 이동에 따른 상기도 변화)

  • Kim, Yong-Il;Park, Soo-Byung;Kim, Jong-Ryoul
    • The korean journal of orthodontics
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    • v.38 no.2
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    • pp.121-132
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    • 2008
  • Objective: The purpose of this study was to evaluate the upper airway dimensional change according to maxillary superior movement after orthognathic surgery and to identify the relationship between the amount of maxillary movement and upper airway dimensional changes. Methods: The samples consisted of 24 adult patients (9 males and 15 females) who had a skeletal discrepancy and had received presurgical orthodontic treatment. They underwent Le Fort I superior impaction osteotomy and mandibular setback surgery. Cephalometric x-rays were taken at 3 stages - T0 (before orthognathic surgery), T1 (just or within 2 weeks after orthognathic surgery), T2 (6 months after surgery) Results: 1, Pharyngeal airway space (PAS (R)-nasopharynx) was decreased after surgery (T1) but recovered at 6 months after surgery; 2, Pharyngeal airway space (PAS (NL)-palatal plane) was increased after surgery and at 6 months after surgery; 3, Pharyngeal airway space (PAS (OL)-occlusal plane) was increased at T1 and was decreased at T2; 4, Soft palate thickness was increased at T1 but it became the same or thinner at T2; 5, There is no statistically significant relation between the amount of maxillary superior movement and pharyngeal airway space. Conclusions: These findings suggested that the maxillary superior movement of about an average of $4.40{\pm}1.14 mm$ did not affect upper pharyngeal airway space changes.

Effects of Jeopgolsan (JGS) Extract on Fracture Healing (접골산(接骨散)이 골절치유에 미치는 영향)

  • Lee, Han-Gil;Oh, Min-Seok
    • Journal of Korean Medicine Rehabilitation
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    • v.28 no.1
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    • pp.1-17
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    • 2018
  • Objectives The purpose of this study was to evaluate the effect of Jeopgolsan (JGS) extract on anti-oxidant, anti-inflammatory activities in RAW 264.7 cells and on factors related with fracture healing in skull fractured rat. Methods Experimental animals were divided into four groups: normal group without any treatment (Normal), contral group were treated orally with distilled water (Control), Experimental group were treated orally with JGS at a concentration of 200 mg/kg/day (JGS 200) and Experimental group were treated orally with JGS at a concentration of 200 mg/kg/day (JGS 400). Rats in each group except the normal group were induced fractures in the skull. The 1,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity were measured to evaluate antioxidant activity. The production of nitric oxide (NO), $interleukin-1{\beta}$ ($IL-1{\beta}$), interleukin-6 (IL-6) and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) in the RAW 264.7 cells were measured to evaluate anti-inflammatory activity. The production of osteocalcin calcitonin, carboxy-terminal telepeptides of type II collagen (CTX II), transforming growth $factor-{\beta}$ ($TGF-{\beta}$), bone morphogenetic protein-2 (BMP-2), Insulin and alkaline phosphatase (ALP) in serum of rats were measured to evaluate the effects of fracture healing at 0, 2, 4, and 6th week. X-rays were taken every 3 week from 0 to 6th week to evaluate fracture healing effect. Results 1. No cytotoxicity was observed. 2. DPPH and ABTS radical scavenging activity were increased in a concentration dependent manner, indicating anti-oxidant effect. 3. NO, $IL-1{\beta}$, IL-6, and $TNF-{\alpha}$ were not significantly changed, indicating no anti-inflammatory effect. 4. Osteocalcin, Calcitonin, $TGF-{\beta}$ and ALP were significantly increased in the experimental groups. 5. CTX II, insulin were significantly decreased in the expermental groups. 6. Radiologic examination showed that union of fracture was promoted. Conclusions From above results, JGS showed significant results in factors related with fracture healing and radiologic examination. Threfore, JGS is expected to be effective in the treatment of fracture.

Operative Treatment of Displaced Proximal Humerus Fractures with the Angular Stable Locking Compression Plate (각안정 잠김 압박 금속판을 이용한 전위된 근위 상완골 골절에 대한 수술적 치료)

  • Kim, Dong-Wook;Kim, Chong-Kwan;Jung, Sung-Won;Kim, Hyeon-Soo
    • Clinics in Shoulder and Elbow
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    • v.14 no.1
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    • pp.27-34
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    • 2011
  • Purpose: We examined the clinical and radiological outcomes for displaced proximal humerus fractures that were treated with a PHILOS angular stable plate. Materials and Method: Forty four patients who underwent surgery between March 2007 and February 2010 were included in this study. All the cases were followed up for an average of 12 months. All the patients were examined and interviewed using the Visual Analog Scale (VAS) score, the Constant score and standardized X-rays to check the neck-shaft angle (NSA) and the presence of medial support. Results: The average Visual Analog Scale score was 2.8 points and the average Constant score was 70.5 points. The average neck shaft angle was $122.5^{\circ}$ and this was statistically significant between the good result group and the poor result group. There were 36 cases of the presence of medial support and 8 cases of the absence of medial support and the difference was statistically significant. Complications such as fixation failure happened in 12 cases. Conclusion: PHILOS angular stable plate fixation as an operative treatment for displaced proximal humerus fractures is a good and reliable treatment option.

Study on a moir$\acute{e}$ Artifact in the Use of Carbon Interspaced Antiscatter Grids for Digital Radiography (탄소 중간물질 그리드를 사용한 DR system에서의 moir$\acute{e}$ artifact에 관한 연구)

  • Lee, Sung-Ju;Cho, Hyo-Sung;Choi, Sung-Il;Cho, Hee-Moon;Oh, Ji-Eun;Lee, So-Young;Park, Yeon-Ok;Lee, Min-Sik
    • Journal of the Korean Society of Radiology
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    • v.2 no.4
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    • pp.5-9
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    • 2008
  • Antiscatter grids are widely used in radiography to remove scattered X-rays and thus improve the image contrast. However, the use of grids makes moir$\acute{e}$ artifact in the digital image, and this can be a critical reason for a mistaken diagnosis. In this paper, we examined that moire artifacts are how to relate with grid frequency, pixel pitch and grid rotation angle. To experiment we prepared 6 grids having different line frequencies (4.0 to 8.5lines/mm) and tested with a DR imager having a $139{\mu}m{\times}139{\mu}m$ pixel size. In the result of this experiment, we could get data about moir$\acute{e}$ artifact that could be make solution to remove the line artifact for the successful use of the grid in digital radiography. The acquired data and theory through this experiment, are expected to make contribution to the elimination of moir$\acute{e}$ artifact in the DR system.

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A Retrospective Clinical Survey of Vertebral Compression Fractures

  • Oh, Ji Hye;Lee, Yun Kyu;Kim, Jae Soo;Lee, Hyun Jong;Lim, Sung Chul
    • Journal of Acupuncture Research
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    • v.35 no.4
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    • pp.219-225
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    • 2018
  • Background: The purpose of this study was to review whether Korean medicine treatment was effective to maintain the spinal stability and to relieve spinal symptom by reviewing medical records of 18 vertebral compression fracture patients. Methods: The subjects were 18 thoracolumbar compression fracture patients who were taken more than two lateral view x-rays of fractured vertebra from Jan, 2010 to June, 2018. They were divided into two groups: the time admitted into Department of Acupuncture & Moxibustion Medicine, Pohang Korean Medical Hospital of Daegu Hanny University from onset (Research 1) and whether or not they have a past history of osteoporosis (Research 2). Then, they were follow-up observed and compared by compression ratio and numerical rating scale (NRS) and so on. Results: The amount of weekly compression rate increase of 18 patients was 1.76% per week. According to the result of Research 1, the patients group (14 patients) who were admitted into the hospital within 1-2 weeks from getting injury was 1.88% per week whereas the patients group(4 patients) who were admitted into the hospital within 3-4 weeks from getting injury was 1.22% per week. By Research 2 result, the patients group (7 patients) who had been diagnosed as an osteoporosis patient was 2.19% per week, and those (11 patients) who had not was 1.49% per week. There was a statistical significance in the change of the amount of compression rate increase in the case of Research 1, but there was not in the case of Research 2. NRS was decreased without significant difference regardless of the time admitted into the hospital and whether or not the patients had the past history of osteoporosis. Conclusion: Considering that there were more amount of compression rate increase at 1-4 weeks from onset, it is necessary to offer treatment more actively on early time from onset. Further research is needed into the increase of compression rate by the patients' having a past history of osteoporosis or not. Given that NRS decreased without significant difference, it is assumed that Korean medicine treatment has a meaningful effect on relieving subjective symptom of patients who are diagnosed as vertebral compression fractures.

Treatment and posttreatment changes following intrusion of maxillary posterior teeth with miniscrew implants for open bite correction (Miniscrew implant를 이용한 상악 구치부 압하와 개방교합 치료의 효과 및 안정성)

  • Lee, Han-Ah;Park, Young-Chel
    • The korean journal of orthodontics
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    • v.38 no.1
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    • pp.31-40
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    • 2008
  • Objective: This study investigated the skeletal and dentoalveolar changes after intrusion of maxillary posterior teeth using miniscrew implants during the treatment and posttreatment period. Method: The subjects consisted of 11 adults (1 male, 10 females) whose open bites were treated by posterior teeth intrusion with miniscrew. The lateral cephalometric x-rays of pre-treatment, post-treatment, and the retention period were evaluated. Results: The average intrusion of maxillary posterior teeth at the end of the treatment period was 2.22 mm (p < 0.001) and the average extrusion of maxillary posterior teeth at the end of the 17.4 month retention period was 0.23 mm (p = 0.359). The relapse rate was calculated at 10.36%. A decrease in overbite after the 17.4 month retention period was 0.99 mm (p < 0.05). The relapse rate was calculated at 18.10%. The skeletal changes and vertical height change of maxillary posterior teeth during the retention period was statistically insignificant, but there was a significant decrease in overbite (mean 0.99 mm, p < 0.05). The amount of intrusion and the overbite improvement from treatment significantly correlates to the degree of relapse. Conclusions: The results indicate that intrusion of the maxillary posterior teeth using miniscrews is an effective, non-surgical treatment modality which can reasonably be used to address adult open bite.

Medical Exposure of Korean by Diagnostic Radiology and Nuclear Medicine Examinations (진단방사선 및 핵의학 검사에 의한 한국인의 의료상 피폭)

  • Kwon, Jeong-Wan;Jeong, Je-Ho;Jang, Ki-Won;Lee, Jai-Ki
    • Journal of Radiation Protection and Research
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    • v.30 no.4
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    • pp.185-196
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    • 2005
  • Although medical exposure from diagnostic radiology procedures such as conventional x-rays, CT and PET scans is necessary for healthcare purposes, understanding its characteristics and size of the resulting radiation dose to patients is much of worth because medical radiation constitutes the largest artificial source of exposure and the medical exposure is in a trend of fast increasing particularly in the developed society. Annual collective doses and per-caput effective doses from different radiology procedures in Korea were estimated by combining the effective dose estimates per single medical procedure and the health insurance statistics in 2002. Values of the effective dose per single procedure were compiled from different sources including NRPB reports, ICRP 80, MIRDOSE3.1 code and independent computations of the authors. The annual collective dose reaches 27440 man-Sv (diagnostic radiology: 22880 man-Sv, nuclear medicine: 4560 man-Sv) which is reduced to the annual per-caput effective dose of 0.58 mSv by dividing by the national population of 47.7 millions. The collective dose is far larger than that of occupational exposures, in the country operated 16 nuclear power plants in 2002, which is no more than 70 man-Sv in the same year. It is particularly noted that the collective dose due to CT scans amounts 9960 man-Sv. These results implies that the national policy for radiation protection should pay much more attention to optimization of patient doses in medicine.