• 한국산학기술학회논문지
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• 제12권7호
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• pp.3117-3122
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• 2011

머리부 전후방향촬영은 종래의 증감지-필름 방사선촬영보다 디지털방사선촬영 시 입사표면선량(ESD)이 훨씬 높다. 따라서 본 연구의 목적은 부가필터를 사용하여 환자의 피폭선량을 줄이기 위한 것이다. 본 연구에서는 머리부 팬톰을 이용하여 머리부 전후방향촬영 시 부가여과판의 두께에 따른 선량 감소효과를 알아보았고, 동시에 부가여과판 사용에 따른 영상의 질적 저하의 평가를 위한 실험을 진행하였다. 선량측정은 머리부 팬톰을 머리부 전후방향촬영자 세로 위치시켜 입사표면선량과 투과선량을 0.1 mmAl으로부터 0.5 mmCu+2.0 mmAl까지 16종류의 부가여과판을 바꾸어 가며 측정하였다. 영상의 화질 평가를 위해서 총 17매의 영상을 촬영하였고 촬영된 영상은 영상의학과 전문의에게 평가를 의뢰하였다. 그 결과 부가여과판 중 0.2 mmCu+1.0 mmAl의 복합여과판을 사용한 부가여과판까지 진단적 가치가 있는 영상을 얻었고, 이 때 머리부 팬톰에 입사표면선량은 약 0.6 mGy이었다. 이 값은 국제원자력기구(IAEA)에서 권고하고 있는 머리부 후전방향촬영 시 입사표면선량 5 mGy의 12%에 불과하였다. 따라서 검사부위에 따라 적정한 부가여과판의 사용으로 환자의 피폭선량을 상당히 감소시키는 효과를 얻을 수 있다.

• 치과방사선
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• 제4권1호
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• pp.31-37
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• 1974

The author has studied roentgenographic images of temporomandibular articulation using various conventional roentgenographies. The roentgenographic images have obtained by application of the contrast media on the glenoid fossa and condylar head in a human dry skull. Comparing the various roentgenograms by Modified Transcranial projection, A-P T.M. articulation projection, Reverse Towne projection, Mayer projection and Bregma-Menton projection. The author has drawn following results. 1. The sharp radiogaphic details were obtained by all technics used except the Bregma-Menton projection, which seemed to be impractical to the study of T.M.J. because of to be shortened the image of condylar head. 2. The best image of the condyle-fossa relationship was appeared by Modified Transcranial projection and better image was acquired by Orbito-Ramus projection, but there were all inferior in Reverse Towne projection, Mayer projection and Bregma-Menton projection. 3. In all of the above techniques, the radiographic images of condylar head were clear and were appeared to be the convex type in Modified Transcranial projection, the angled type in Orbito-Ramus and Reverse Towne projection, the flat type in Mayer projection and the distorted angled type in Bregma-Menton projection. 4. The radiographic image of condylar head was shortened in Bregma-Menton projection only and was magnified somewhat in other projection.

• 대한방사선기술학회지:방사선기술과학
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• 제3권1호
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• pp.21-27
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• 1980

It is the experimental report by using 17cm, 19cm in thickness water-phantom to investigate optimum tube voltage in taking skull roentgenography. The obtained results are as follows: 1. An adequate kVp for P-A projection is range from 80-90. 2. An adequate kVp for lateral projection is range from 75-85.

• 대한방사선기술학회지:방사선기술과학
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• 제44권4호
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• pp.301-306
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• 2021

The skull has peripheral organs such as the crystalline lens and thyroid gland, which are highly radiosensitive, but the examination is performed without considering the uneven dose distribution due to the heel effect at the time of the current Skull Town's examination. However, no studies have been conducted on the exposure dose of surrounding organ tissues due to the difference in image density due to the heel effect and the non-uniformity of the dose. Using the cathode (-) and anode (+) set on the Tube to measure the scattered radiation along the Tube direction as a guide, change 30° and 37° in the cathode direction and 30° and 37° in the anode direction. It was given and investigated 5 times to obtain scattered radiation. image measurements were SNR, PSNR, RMSE, and MAE. Measurement results Measurement results of surrounding organ doses when the Tube direction was 30° and 37° The dose was low when the direction was cathodic in all organs (p<0.000). Both cathodes were higher in the image measurements(p<0.04). Continuous research may be needed for diagnostically valuable imaging and minimization of patient exposure dose.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권6호
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• pp.622-627
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• 2008

In orthognathic surgery, precise analysis and diagnosis are essential for successful results. In facial asymmetric patient, traditional 2D image analysis has been used by lateral and P-A Cephalometric view, Skull PA, Panorama, Submentovertex view etc. But clinicians sometimes misdiagnose because they cannot find exact landmark due to superimposition, moreover image can be magnified and distorted by projection technique or patient's skull position, when using these analysis and method. For overcome these defects, analysis by using of 3D CT has been introduced. In this way we can analysis precisely by getting the exact image free of artifact and finding exact landmark with no interruption of superimposition. So we want to review of relationship between various skeletal landmarks of mandible or cranial base and facial asymmetry by predictable analysis using 3D CT. We select the cases of the patients who visited our department for correction of facial asymmetry during 2003-2007 and who were taken image of 3D CT for diagnosis. 3D CT images were reconstructed to 3D image by using V-Work program (Cybermed Inc., Seoul, Korea). And we analysis the relationship between facial asymmetry and various affecting factor of skeletal pattern. The mandibular ramus hight difference between right and left was most affecting factor that express facial asymmetry. And in this research, there was no relationship between cranial base and facial asymmetry. The angulation between facial midline and mandibular ramus divergency has significant relationship with facial asymmetry