• Title/Summary/Keyword: 망막

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The Effect of Laser Irridation on the Ultrastructure of Retina (Laser 조사가 망막의 미세구조에 미치는 영향)

  • Kim, Douk Hoon;Mun, Jung Hak
    • Journal of Korean Ophthalmic Optics Society
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    • v.1 no.1
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    • pp.15-22
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    • 1996
  • The fine structure of retinal tissue was studied to investigate on effect of Laser irridation on the ICR mouse with electron microscope. The results obtained were as follows: 1. At the normal groups, the most retinal layers were a complex structure, consisting of several specific cells and nerve fiver. 2. In the increasing time of Laser irridation, each cell layer of retina was not uniform of the structure and band. The visual cells were severely heterochromatin swelling of cytoplasm, irregular shape & heterochromatin of nuclear, and disappear of some cytoplasm. The nucleus and nerve fiber of retinal layer was a very irregular shape, formation of vesicle, not identify of each intercellular boundary. The pigment epithelial cells were not an uniform, a large vesicle formation of cytoplasm, and a condensation & very irregular shape of nucleus.

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Bayesian Network-based Data Analysis for Diagnosing Retinal Disease (망막 질환 진단을 위한 베이지안 네트워크에 기초한 데이터 분석)

  • Kim, Hyun-Mi;Jung, Sung-Hwan
    • Journal of Korea Multimedia Society
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    • v.16 no.3
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    • pp.269-280
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    • 2013
  • In this paper, we suggested the possibility of using an efficient classifier for the dependency analysis of retinal disease. First, we analyzed the classification performance and the prediction accuracy of GBN (General Bayesian Network), GBN with reduced features by Markov Blanket and TAN (Tree-Augmented Naive Bayesian Network) among the various bayesian networks. And then, for the first time, we applied TAN showing high performance to the dependency analysis of the clinical data of retinal disease. As a result of this analysis, it showed applicability in the diagnosis and the prediction of prognosis of retinal disease.

A study on Image Recognition based on the Characteristics of Retinal Cells (망막 세포 특성에 의한 영상인식에 관한 연구)

  • Cho, Jae-Hyun;Kim, Do-Hyeon;Kim, Kwang-Baek
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.10a
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    • pp.393-397
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    • 2007
  • 최근 시각 장애인을 위한 인공망막 모델 구현에 관한 연구 중 시피질 자극기 기술은 시각 자극 전달의 중간 단계를 생략하고 직접 뇌세포를 자극하는 것이다. 본 논문에서는 망막에서 시각 피질로 시각정보를 전달할 때 발생하는 시각 피질의 특성, 즉 방향성에 대한 반응 특성을 특징 데이터로 구성하여 인식함으로써 인간 시각 정보 처리와 유사한 영상 추출 및 인식 모델을 제안한다. 제안된 방법은 영상의 특징을 추출 한 후 Delta-bar-delta 기반 오류 역전파 알고리즘을 적용하여 영상의 특징들을 인식한다. 제시된 방법의 성능을 분석하기 위하여 다양한 숫자 패턴들을 대상으로 실험한 결과, 제안된 망막 세포로부터 전달된 정보를 방향성에 대한 민감성을 고려하여 영상의 특성을 추출하여 인식하는 모델이 기존의 영상 추출 및 인식 모델보다 인식률에 있어서는 별 차이가 없지만 다양한 실험에서 확인할 수 있듯이 인간 시각과 같이 인식 성능이 민감하지 않는 것을 알 수 있었다.

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당뇨병에서 나타나는 눈의 변화-당뇨병성 망막증

  • Son, Jun-Hong
    • The Monthly Diabetes
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    • s.221
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    • pp.11-12
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    • 2008
  • 당뇨병으로 나타나는 눈의 변화는 여러 가지가 있지만 그 중 가장 심각하고 중요한 것은 망막증이다. 당뇨병은 미세혈관계에 장애를 일으키기 때문에 수많은 미세혈관에 의해 시기능을 유지하고 있는 눈에서 그 합병증이 두드러지게 나타난다.

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Clinical Results of Silicone Oil Injection following Vitrectomy as a Primary Procedure in Retinal Detachment (망막박리에서 일차수술로 유리체절제술과 실리콘 주입술에 대한 임상결과 분석)

  • Gyeong, Gil-Hyeon;Lee, Moo-Sik;Hwang, Hye-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.12
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    • pp.3919-3924
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    • 2009
  • To evaluate clinical results of silicone oil injection for retinal detachment. The 45 eyes of 44 patients underwent vitrectomy and silicone oil injection from 1999 to 2002. 1.There were no history of previous retinal surgery and ocular trauma. In 24 of the 45 eyes(53%) visual acuity increased and stabilized in 18 of the 45 eyes(40%). 2. 1 of 16 eyes(6.3%) had recurred retinal detachment after silicone oil removal. 3. Final retinal reattachment was achieved in 44 eyes(97%). Postoperative complications were cataract(16 eyes), glaucoma(10 eyes), emulsification of silicone oil(5 eyes), keratopathy(2 eyes) and recurrent retinal detachment(1 eye). These results show that silicone oil injection for primary retinal detachment yields a high rate of anatomic success and the good visual outcome

De-Noising of Electroretinogram Signal Using Wavelet Transforms (웨이브렛 변환을 이용한 망막전도 신호의 잡음제거)

  • Seo, Jung-Ick;Park, Eun-Kyoo
    • Journal of Korean Ophthalmic Optics Society
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    • v.17 no.2
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    • pp.203-207
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    • 2012
  • Purpose: Electroretinogram(ERG) signal noise as well as conducting other bio-signal measurement were generated. It was intened to enhance the accuracy of retinal-related diagnosis with removing signal noise. Methods: Sampling signal was made with generating 60 Hz noise and white noise. The noise were removed using wavelet transforms and bandpass filter. De-noising frequency was compared with Fourier transform spectrum. Removed noises were compared numerically using SNR(signal to noise ratio). Results: The result compared Fourier transform spectrum was showed that 60 Hz noise removed completely and most of white noise was removed by wavelet transforms. 60 Hz and the white noise remained using bandpass filters. The result compared SNR showed that wavelet transforms was 22.8638 and bandpass filter was 4.0961. Conclusions: Wavelet transform showed less signal distortion in removing noise. ERG signal is expected to improve the accuracy of retinal-related diagnosis.

Pattern Classification of Retinitis Pigmentosa Data for Prediction of Prognosis (망막색소변성 데이터의 예후 예측을 위한 패턴 분류)

  • Kim, Hyun-Mi;Woo, Yong-Tae;Jung, Sung-Hwan
    • Journal of Korea Multimedia Society
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    • v.15 no.6
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    • pp.701-710
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    • 2012
  • Retinitis Pigmentosa(RP) is a common hereditary disease. While they have been normally living, those who have this symptom feel frustration and pain by the damage of visual acuity. At the national level, the loss of the economic activity due to the reduction of economically active population will be also greater. There is an urgent need for the base study that can provide the clinical prognosis information of RP disease. In this study, we suggest that it is possible to predict prognosis through the pattern classification of RP data. Statistical processing results through statistical software like SPSS(Statistical Package for the Social Service) were mainly applied for the conventional study in data analysis. However, machine learning and automatic pattern classification was applied to this study. SVM(Support Vector Machine) and other various pattern classifiers were used for it. The proposed method confirmed the possibility of prognostic prediction based on the result of automatically classified RP data by SVM classifier.

An Intelligent Decision Support System for Retinal Disease Diagnosis based on SVM using a Smartphone (스마트폰을 이용한 SVM 기반 망막 질병 진단을 위한 지능적인 의사 결정 지원 시스템)

  • Lee, Byung-Kwan;Jeong, Eun-Hee;Tifani, Yusrina
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.8 no.5
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    • pp.373-383
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    • 2015
  • This paper proposes a decision support system to recognizing retinal diseases. This paper uses a smartphone platform and cloud computing as the base of the system. A microscopic lens is attached int' the smartphone camera to capture the user retinal image for recognizing the user's retinal condition. An application is assembled in computer and then installed in to the smartphone. The application role is to connect between the system in smartphone and system in cloud, the application will send the retinal image to the cloud system to be classified. The paper uses OCFE (optimized classifier based on feature elimination) algorithm as the classifier. The retinal image is trained using combination of two ophthalmology databases DIARETDB1 v2.1 and STARE. Therefore, this system average accuracy is 88%, while the average error rate is 12%.

Enhancement of a Choroid Vessel Using Conditional Erosion in ICGA Image (형광안저 조영영상에서 선택적 영역침식을 이용한 맥락막혈관영상 향상)

  • Jung, Ji-Woon;Kim, Pil-Un;Lee, Yun-Jung;Kim, Myoung-Nam
    • Journal of Korea Multimedia Society
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    • v.12 no.8
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    • pp.1073-1081
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    • 2009
  • In this paper, we proposed new method to enhance choroidal vessels by suppressing retina vessels brightness. It is well-known that CNV(choroidal neovascularization) is related with sight loss. The main feature of CNV is the occurrence of new vessels in choroid. Unfortunately, because retina vessels brightness is stronger than choroidal vessels brightness in ICGA(indocynanine green angiography) image, so that the choroidal vessels were hardly recognized. Therefore, for correct diagnosis, the choroidal vessels must be enhanced in ICGA image. The proposed enhancement method consists of 3 strategies. First, the retina vessels were detected by multi scale enhancement technique, hysteresis thresholding, KNN(Kth-nearest neighbor) classification method. And then, a retina vessel mask was generated from detection result. Next, the brightness of retina vessels was suppressed by the proposed conditional region erosion method and mask region until the mask region was vanished. Finally, the brightness of choroidal vessel was enhanced on processed image. Through an experiment, we had confirmed that the proposed method was robust and efficient.

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Acute Phase Retinal Phototoxicity Induced by Blue Fluorescent Light (토끼에서의 청형광 광선에 의한 실험적 급성 망막독성)

  • Park, Young-Hoon;Cha, Soon-Cheol;Hahn, Duk-Kee
    • Journal of Yeungnam Medical Science
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    • v.12 no.1
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    • pp.75-83
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    • 1995
  • Even though phototherapy is an effective means of treating hyperbilirubinemia, adequate binocular shields are essential to prevent light hazard of retina during phototherapy. The phototherapy to young albino rabbits was performed under various conditions; exposured for 12, 24, and 48 hours, continuity or intermittence of irradiation, and use of shields. Although there was no definite pathologic change in indirect ophthalmoscopic examination, severe damage was seen at electron microscopic level. In all experimental groups, swelling and edema of photoreceptor were seen at right after phototherapy. Futhermore, more severe damage was seen in case of intermittent irradiated group and prolong exposed group. In mydriatic eyes, severity of damage was similiar to non mydriatic eyes, but area of retinal damage was more extensive than non-mydriatic eyes. In control group which was protected by binocular shields during phototherapy, no significant abnormality was found.

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