• 제목/요약/키워드: Medical Image Evaluation

검색결과 598건 처리시간 0.029초

CD-RAD Phantom을 이용한 의료영상의 분석 (Analysis of Medical Image with CD-RAD Phantom)

  • 김창복;김영근;최용성;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.369-369
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    • 2007
  • 본 연구에서는 CD-RAD Phantom을 이용하여 의료영상의 명세성 (image clarity)분석을 위하여 동일한 X선 영상을 대상으로 물리적 평가와 시각적 평가를 비교분석 하였다. 측정방법은 CD-RAD Phantom을 X선 조사하여 CR 영상처리장치를 통해 영상을 획득하였으며, 영상분석은 CD-RAD analyser program을 통한 통계학적 방법으로 물리적 평가를 시행하고, 동일한 영상의 시각적 평가는 관찰자 20명을 대상으로 blind test를 시행하였다. 분석결과는 Contrast-detail curve의 물리적 평가 IQF값은 25, 시각적 평가 IQF값은 30으로 분석되어 물리적 평가가 시각적 평가에 비해 우수하게 나타났다. 의료영상의 특성은 영상 판독자에게 영상의 정보 전달능력이 매우 중요하므로 객관적인 물리적 분석법과 시각적 분석법이 병행되어야 한다고 판단된다.

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새로운 발 사방향 검사법의 유용성에 관한 연구 (A Study on the Usefulness of the New Foot Oblique Projection)

  • 김민석;주영철;이승근
    • 대한방사선기술학회지:방사선기술과학
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    • 제44권5호
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    • pp.443-449
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    • 2021
  • In this study, the purpose is to present the foot inclination angle for realizing an image similar to that of the existing examination method and to present the clinical usefulness of the new examination method through comparison between the existing examination method and the newly designed standing foot oblique projection. A foot phantom was used, and the magnification of the image according to the angle was quantitatively evaluated by attaching a nut to the position of the cuboid of the phantom. The internal oblique image acquired using a 30° wedge was set as the standard image. And that image was compared with the images acquired by changing the angle of the foot from 20° to 65° at intervals of 5°. Image evaluation was performed by 3 radiological technologists, and qualitative evaluation using a Likert 5-point scale for evaluation items of true oblique view and quantitative evaluation of the value obtained by measuring the diameter of a nut in each image were performed as image evaluation. For data analysis, reliability analysis between the measure and comparative analysis of the average value for each angle were performed. The qualitative evaluation score for each image was 4.5 to 5 points for most questions in the case of the standard image. And 4 points or less for most questions in the images with a foot angle of 45° or less, and an evaluation score close to the standard image was obtained in the image of 50° or more. And in the quantitative evaluation, the diameter of the nut was measured to be 9.28~9.56 mm. The qualitative evaluation showed a reliability of 0.95~1.0 and the quantitative evaluation was 0.62. As a result of comparing and analyzing the average of the quantitative and qualitative average values for each angle image, the group with the average value most similar to the standard image was images obtained at 55° and 60°, and in the post-analysis, the images of both groups were the same group as the standard image(p<0.01). As a result of this study, it was found that the angle of inclination of the foot for realizing the image most similar to the existing image in the standing foot oblique projection is 55°~60°. In addition, if this test method is applied to the clinic, it is believed that it will help prevent safety accidents such as falls during the test and improve test efficiency by minimizing the movement of patients for the test.

Performance Evaluation of Medical Image Transmission System using TH UWB-IR Technology

  • Lee, Yang-Sun;Kang, Heau-Jo
    • Journal of information and communication convergence engineering
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    • 제4권3호
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    • pp.97-100
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    • 2006
  • In this paper, the transmission service for medical image is proposed via IEEE 802.15.4a on WPAN environment. Also, transmission and receiving performance of medical image using TH UWB-IR system is evaluated on indoor multi-path fading environment. On the results, the proposed scheme can solve the problem of interference from the medical equipment in same frequency band, and minimize the loss due to the indoor multi-path fading environment. Therefore, the transmission with low power usage is possible.

상강화기의 임상평가 (Clinical Evaluation for System Performance of Image Intensifiers)

  • Kim, Chang-Seon;Charles R. Wilson
    • 한국의학물리학회지:의학물리
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    • 제9권3호
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    • pp.143-154
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    • 1998
  • 상강화기는 형광 영상장치에서 영상의 특성을 결정하는 주된 요소이다. 본 연구는 두가지의 상강화기를 임상에서 평가하기 위하여 간단하고 비파괴적이며 적당한 시간내에 행할 수 있는 계의 활동 프로그램을 제시하였다. 이 프로그램은 크게 세 부분 즉, X-선 발생장치, 영상의 질, 조준으로 되어있다. X-선의 발생장치에 대하여 관전압의 정확도와 자동노출 조절기능을 비교하였다. 영상의 질을 위해서는 저대비 및 고대비 분해능 측정, 체격자 실험 등을 수행하였으며 이 실험에서는 비디오 모니터 및 순간영상을 필름화한 정량적인 분석을 분석하였다. 조준에 대해서는 상강화기의 유용한 영역의 직경과 상의 찌그러짐을 측정하고 정량적인 분석을 하였다. 이 실험들의 과정 및 결과들이 상강화기의 인수검사 및 계의 활동지수를 평가하는데 이용되기를 바란다.

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우리나라 현행 한의사 진료가운에 대한 조사연구 (Study on the Present Gown of Oriental Medical Doctors in Korea)

  • 서옥경
    • 복식
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    • 제52권3호
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    • pp.139-147
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    • 2002
  • This study was carried out to survey the contentment of the oriental medical doctors to the present gown which they wear. The objects were the oriental medical doctors who work for the university hospitals and the private clinics. The subjects were mainly the evaluation of the relation to the image of oriental hospital and the gown, the evaluation of the present their gowns and the evaluation on the improvement of their gowns. The collected data were analysed by the frequency, cross-table and $\chi^2$ using SPSS program. The results showed that the oriental medical doctors who work for the university hospital evaluated the difference of the image more important than those who work for the private clinics. Also the former was more than the latter on the necessity of the difference in the gowns between the western and oriental medical doctors. The oriental doctors regarded the tradition as of great importance in the improvement of their gown. More than 70% of them wanted to separate their gown for the spring-summer from that for the autumn-winter.

화상처리 기술을 응용한 의료용 화상의 정량적 평가에 관한 연구 -특징량 추출 및 그 타당성 검토 - (A Study on the Quantitative Evaluation of Medical Images by Using the Technique of Image Processing - Determination and Validation of Features -)

  • 송재욱
    • 한국정보통신학회논문지
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    • 제2권4호
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    • pp.619-626
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    • 1998
  • 본 논문에서는 화상처리 기법을 이용하여 의료용 화상의 정량적 평가 특징에 관하여 기술한 것이다. 의사들로부터 조언을 구하여, 병의 진전과 관련이 깊은 세 가지 특징을 구하고, 각 특징과 의사가 행한 평가치의 비교에 의하여 가슴 X선 사진상의 폐병의 정량적인 평가에 대한 타당성을 확인하였다.

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Side lobe free medical ultrasonic imaging with application to assessing side lobe suppression filter

  • Jeong, Mok Kun;Kwon, Sung Jae
    • Biomedical Engineering Letters
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    • 제8권4호
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    • pp.355-364
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    • 2018
  • When focusing using an ultrasonic transducer array, a main lobe is formed in the focal region of an ultrasound field, but side lobes also arise around the focal region due to the leakage. Since the side lobes cannot be completely eliminated in the focusing process, they are responsible for subsequent ultrasound image quality degradation. To improve ultrasound image quality, a signal processing strategy to reduce side lobes is definitely in demand. To this end, quantitative determination of main and side lobes is necessary. We propose a theoretically and actually error-free method of exactly discriminating and separately computing the main lobe and side lobe parts in ultrasound image by computer simulation. We refer to images constructed using the main and side lobe signals as the main and side lobe images, respectively. Since the main and side lobe images exactly represent their main and side lobe components, respectively, they can be used to evaluate ultrasound image quality. Defining the average brightness of the main and side lobe images, the conventional to side lobe image ratio, and the main to side lobe image ratio as image quality metrics, we can evaluate image characteristics in speckle images. The proposed method is also applied in assessing the performance of side lobe suppression filtering. We show that the proposed method may greatly aid in the evaluation of medical ultrasonic images using computer simulations, albeit lacking the use of actual experimental data.

Quantitative Evaluation of Setup Error for Whole Body Stereotactic Radiosurgery by Image Registration Technique

  • Kim, Young-Seok;Yi, Byong-Yong;Kim, Jong-Hoon;Ahn, Seung-Do;Lee, Sang-wook;Im, Ki-Chun;Park, Eun-Kyung
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.103-105
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    • 2002
  • Whole body stereotactic radiosurgery (WBSRS) technique is believed to be useful for the metastatic lesions as well as relatively small primary tumors in the trunk. Unlike stereotactic radiosurgery to intracranial lesion, inherent limitation on immobilization of whole body makes it difficult to achieve the reliable setup reproducibility. For this reason, it is essential to develop an objective and quantitative method of evaluating setup error for WBSRS. An evaluation technique using image registration has been developed for this purpose. Point pair image registrations with WBSRS frame coordinates were performed between two sets of CT images acquired before each treatment. Positional displacements could be determined by means of volumetric planning target volume (PTV) comparison between the reference and the registered image sets. Twenty eight sets of CT images from 19 WBSRS patients treated in Asan Medical Center have been analyzed by this method for determination of setup random error of each treatment. It is objective and clinically useful to analyze setup error quantitatively by image registration technique with WBSRS frame coordinates.

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피부병변의 정량적 평가를 위한 디지털 컬러 영상 시스템 (Digital Color Imaging Systems for Quantitative Evaluation of Skin Lesions)

  • 한병관;정병조
    • 대한의용생체공학회:의공학회지
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    • 제28권2호
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    • pp.195-198
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    • 2007
  • In this paper, we introduce a digital cross-polarization and fluorescent color imaging system for quantitative evaluation of skin lesions. We describe the characterization of the imaging systems and the quantitative image analysis methods to show the feasibility for quantitative evaluation of skin lesions. The polarization color image was used to compute erythema and melanin index image which are useful for quantitative evaluation of pigmentation and vascular skin lesions, respectively. The fluorescent color image was used to quantitatively evaluate "sebum" and "vitiligo". In quantitative evaluation of various skin lesions, we confirmed the clinical efficacy of the imaging systems for dermatological applications. Finally, we sure that the imaging systems can be utilized as important assistant tools for the evaluation of skin lesions by providing reproducible quantitative result for widely distributed skin lesions.

Usefulness of Temporal Subtraction for The Detection of Interval Changes of Interstitial Lung Diseases on Chest Radiographs

  • Higashida, Yoshiharu;Ideguchi, Tadamitsu;Muranaka, Toru;Akazawa, Fumio;Miyajima, Ryuichi;Tabata, Nobuyuki;Ikeda, Hirotaka;Ohki, Masafumi;Toyofuku, Fukai;Doi, Kunio
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.454-456
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    • 2002
  • The evaluation of interval changes between temporally sequential chest radiographs is necessary for the detection of new abnormalities or interval changes, such as pulmonary nodules and interstitial disease. For interstitial lung disease, the interval changes are very important for diagnosis and treatment. Especially, interstitial lung disease may show rapid changes in the radiographs, show changes in the entire lung field in minute detail, or show changes in multiple parts depending on the type. It is therefore difficult to have an accurate grasp of the condition of the disease only with conventional radiographs. The temporal subtraction technique which was developed at the University of Chicago, provides a subtraction image of the current warped image and the previous image. A temporal subtraction image, shows only differences and changes between the two images, can be very useful for a diagnosis of interstitial lung disease. However, the evaluation of the temporal subtraction technique for interstitial lung disease using receiver operating characteristic(ROC) studies has not been reported yet. Therefore, we have evaluated the clinical usefulness of a temporal subtraction technique for detection of interval changes of interstitial lung disease by ROC analysis.

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