• Title/Summary/Keyword: 시신경

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Optic Nerve Decompression for Traumatic Optic Neuropathy: A Case Report (외상성 시신경병증의 시신경 감압술을 통한 치험례)

  • Hyun, Kyung Bae;Kim, Sun Ho;Choi, Jong Woo;Kim, Yong Oock;Park, Beyoung Yun
    • Archives of Plastic Surgery
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    • v.32 no.3
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    • pp.389-392
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    • 2005
  • A case of visual loss following cranio-maxillofacial trauma is reported. The patient had acute optic nerve injury associated with a fracture of the right zygomaticomaxillary and fronto-naso-ethmoido-orbital bone and epidural hematoma on the right temporal lobe of brain. Bony fragments compressing the optic nerve on lateral side was identified on computed tomography. Decompression of the optic nerve combined with evacuation of epidural hematoma has been performed via transfrontal craniotomy. The patient had complete recovery of visual acuity without any complications. The role of optic nerve decompression in the management of patients with traumatic optic neuropathy is discussed. Surgical indication is controversial and the procedure should be considered only within the context of the specific indication of the individual patient.

Ultrastructure of Ocellar Never System in Drosophila melanogaster (초파리 단안 신경계의 미세형태학적연구)

  • 윤춘식
    • Journal of Life Science
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    • v.9 no.6
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    • pp.709-714
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    • 1999
  • Ultrastructure of ocellar system was studied in adult Drosophila melanogaster. Ocellus was composed of terminal receptors, interneuron and glia. These three part showed different brightness each other and each component was distinct. In the glial cell, rER was abundant, and terminal receptors and interneuron showed numerous microtubules, special transporting system. The terminal receptors have particular structure referred as capital projection connecting the terminal receptor to glia. In synaptic active zone between terminal receptor and interneuron, ribbon-like structures and synaptic vesicles around the structures were frequently observed. In addition, the cross section of giant interneuron was also observed.

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The Center Locus Estimation of the Evoked Potential Distributions During Visual Stimulation in Human (시각 자극 동안의 유발성 전위분포 의 중심점 추적에 관한 연구)

  • Park, Gwang-Seok;Min, Byeong-Gu;Lee, Chung-Ung
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.20 no.3
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    • pp.6-12
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    • 1983
  • The visual evoked potentials were measured using 19 electrodes attached to the scalp in 5 normal and 4 abnormal subjects during visual stimulation and these data were sampled for computer processing with 500 Hz sampling frequency. The center of potential distributions and its time-dependent locus were estimated from these potential distributions using weighting matrix which was determined by the electrodes' position coordinates. In normal subjects these estimated electrical signals were shown to propagate from the frontal lobe to the occipital lobe of the cortex following the known visual pathway. In abnormal subjects, there were significant differences in these estimated propagation pathway. The relationships among this model, the point source model and the dipole source model were analyzed.

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The Development of an Alignment algorithm for the Log-polar Image-based 2D Object Recognition (Log-polarImage를 기반으로한 이차원 물체인식을 위한 Alignment algorithm개발)

  • Son, Young-Ho;You, Bum-Jae;Oh, Sang-Rok;Park, Gwi-Tae
    • Proceedings of the KIEE Conference
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    • 2003.07d
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    • pp.2471-2473
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    • 2003
  • 인간의 안구는 색과 모양을 식별하는 데에 관여하는 원추 세포와 물체의 명암을 구분하는 간상 세포로 구성되어지는 시세포를 가진다. 망막 위에 분포되어 있는 시세포들은 시축을 중심으로 각기 다른 밀도로 분포 되어 있다. 특히 광축과 만나는 중심 지역은 Fovea라고 하는 직경 1mm 정도의 작은 우물을 이루고 있는데 원추 세포들이 고해상도로 분포되어 있고 시신경과 일대일로 연결되어 있어 시각 처리의 중심이 된다. 특히, 글자나 물체를 인식하기 위해 인간은 대상물을 응시하여 대상물의 영상이 Fovca영역에 맺히도록 추적 운동을 계속한다. 본 논문에서는 인간의 눈과 유사한 망막 모델의 하나인 Log-polar Image를 이용한 물체 인식을 위해 물체를 Log-polar Image Plane의 중심에 위치시키기 위한 모멘텀(Momentum)기반 정합 알고리즘(Alignment Algorithm)을 제시한다. 이는 눈동자 운동이 가능한 능동형 시각 장치의 Tracking 및 Pursuit 동작 중에 밭생하는 추적 오차를 보상함으로써 운동 중에도 효과적인 물체 인식이 가능하게 한다. 또한, 물체를 Log-polar Image Plane의 중심에 위치시킴으로써 물체의 위치 이동, 회전이동 그리고 크기 변화에 무관하게 물체를 인식한 수 있음을 제시한다.

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A case report of reduced papilledema in a Vogt-Koyanagi-Harada syndrome patient with herbal medicine (보그트-고야나기-하라다병 환자에서 한약 단독치료로 시신경유두 부종이 감소한 치험 1례)

  • Lee, Dong-Jin;Kwon, Kang;Seo, Hyung-Sik
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.27 no.2
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    • pp.83-88
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    • 2014
  • Objectives : Vogt-Koyanagi-Harada(VKH) syndrome is a multisystem autoimmune disease characterized by its affects on pigmented tissues in the ocular, auditory, integumentary and central nervous system. This case is to report a decreased optical disc swelling in VKH patient treated only with herbal medication. Methods : A 56-year-old male patient with VKH experienced headache and numbness during 7 months of steroid treatment. He visited our clinic and was administered Haeulsoyo-san (解鬱逍遙散) three times a day for a month. No other oriental or western treatments were included. Result & Conclusions : Patient didn't complain any discomfort during the treatment. Significantly decreased optical disc swelling was confirmed by taking fundus photo. This is the first case of KVH to be reported in Korean medicine society.

Retinal Blood Vessel Segmentation using Deep Learning (딥러닝 기법을 이용한 망막 혈관 분할)

  • Kim, Beomsang;Lee, Ik Hyun
    • The Journal of Korean Institute of Information Technology
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    • v.17 no.5
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    • pp.77-82
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    • 2019
  • Diabetic retinopathy is a complicated form of diabetes due to circulatory disorder in the peripheral blood vessels of the retina. We segment the microvessel for diagnosing diabetic retinophathy. The conventional methods using filter and features can segment the thick blood vessels, but it has relatively weak for segmenting fine blood vessels. In pre-processing step, noise reduction filter and histogram equalization are applied to suppress the noise and enhance the image contrast. Then, deep learning technique is used for pixel-by-pixel segmentation. The accuracy of conventional methods is between 90% to 94%, while the proposed method has improved as 95% accuracy. There is a problem of segmentation error around the optic disc and exudate due to the network depth. However the accuracy can be improved by modifying the network architecture in the future.

Dose Planning of Forward Intensity Modulated Radiation Therapy for Nasopharyngeal Cancer using Compensating Filters (보상여과판을 이용한 비인강암의 전방위 강도변조 방사선치료계획)

  • Chu Sung Sil;Lee Sang-wook;Suh Chang Ok;Kim Gwi Eon
    • Radiation Oncology Journal
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    • v.19 no.1
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    • pp.53-65
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    • 2001
  • Purpose : To improve the local control of patients with nasopharyngeal cancer, we have implemented 3-D conformal radiotherapy and forward intensity modulated radiation therapy (IMRT) to used of compensating filters. Three dimension conformal radiotherapy with intensity modulation is a new modality for cancer treatments. We designed 3-D treatment planning with 3-D RTP (radiation treatment planning system) and evaluation dose distribution with tumor control probability (TCP) and normal tissue complication probability (NTCP). Material and Methods : We have developed a treatment plan consisting four intensity modulated photon fields that are delivered through the compensating tilters and block transmission for critical organs. We get a full size CT imaging including head and neck as 3 mm slices, and delineating PTV (planning target volume) and surrounding critical organs, and reconstructed 3D imaging on the computer windows. In the planning stage, the planner specifies the number of beams and their directions including non-coplanar, and the prescribed doses for the target volume and the permissible dose of normal organs and the overlap regions. We designed compensating filter according to tissue deficit and PTV volume shape also dose weighting for each field to obtain adequate dose distribution, and shielding blocks weighting for transmission. Therapeutic gains were evaluated by numerical equation of tumor control probability and normal tissue complication probability. The TCP and NTCP by DVH (dose volume histogram) were compared with the 3-D conformal radiotherapy and forward intensity modulated conformal radiotherapy by compensator and blocks weighting. Optimization for the weight distribution was peformed iteration with initial guess weight or the even weight distribution. The TCP and NTCP by DVH were compared with the 3-D conformal radiotherapy and intensitiy modulated conformal radiotherapy by compensator and blocks weighting. Results : Using a four field IMRT plan, we have customized dose distribution to conform and deliver sufficient dose to the PTV. In addition, in the overlap regions between the PTV and the normal organs (spinal cord, salivary grand, pituitary, optic nerves), the dose is kept within the tolerance of the respective organs. We evaluated to obtain sufficient TCP value and acceptable NTCP using compensating filters. Quality assurance checks show acceptable agreement between the planned and the implemented MLC(multi-leaf collimator). Conclusion : IMRT provides a powerful and efficient solution for complex planning problems where the surrounding normal tissues place severe constraints on the prescription dose. The intensity modulated fields can be efficaciously and accurately delivered using compensating filters.

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Evaluation of usefulness of multi directional angles oblique scan method in optic nerve MRI (시각신경 MR 검사 시 다중 각도 스캔 기법의 유용성 평가)

  • Cho, Moo-Seong;Cho, Jae-Hwan;Bae, Jae-Yeong;Kim, Jeong-Soo;Kim, Kyeong-Keun
    • Journal of the Korean Society of Radiology
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    • v.5 no.4
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    • pp.161-169
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    • 2011
  • This research experimented on the change of the multiple colleague scan angle facing one scan object facet to many directions of the form of 3D about the visual angle nervous system forming the cubic distribution with the gradient magnetic field of the mri system and considered the existing basic angle oblique direction test coverage and comparison. MR system can freely select various pulse sequence and image slice. To oblique imaging for optic nerve viewing, we have studied the variation of scan angle between typical oblique scan method (sagittal-coronal plane) and multi directional angles oblique scan method (sagittal-coronal-axial plane) using gradient of MR system. In this study, the subjects of the experiment were normal adults in our country. As a result, we confirmed that multi directional angles oblique scan method can display anatomical information of more wider area than typical oblique scan method. In addition, to clearly display optic nerve, we also confirmed that image slice thickness and pulse sequence have effect on it.

Performance Comparison of Modulation Schemes according to the Dimming Control in MIMO-VLC System (MIMO-VLC에서 디밍제어에 따른 변조방식들의 성능 비교)

  • Lee, Min-Jung;Lee, Byung-Jin;Ju, Sang-Lim;Kim, Yong-Won;Kim, Kyung-Seok
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.4
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    • pp.63-69
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    • 2014
  • Visible light communication is a communication method using an LED's blinking(ON/OFF), it has a feature of light because of the limit of perception by the human's optic nerve. LED' dimming control used in the VLC system is important factor needed to provide energy saving and life benefits. With advances in VLC system, MIMO technology has received much attention in that it can be obtain channel capacity proportionate to the number of antenna. Therefore, in this paper, with RC method which is one of the MIMO style in VLC system, it is compared communication performance using RZ-OOK, VPPM, MPPM and OPPM. As a result of the simulation was run against this, MPPM works well in terms of Power requirement and OPPM works well in terms of Spectral efficiency and Bandwidth requirement, also it was confirmed that there is a significant impact on the communication performance of each modulation scheme according to the dimming.

Rhythms and Biological Clock (리듬과 생체시계)

  • Choi Donchan
    • Development and Reproduction
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    • v.7 no.1
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    • pp.1-7
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    • 2003
  • Most animals, including human beings, live in a cyclic pattern of lift that is influenced by the ambient changes of environment. The regular changes occurred by rotation of the Earth itself its revolving around the Sun, and the local environment, are reflected by the distinct behavior in the living organisms. These regular changes of environment have been imprinted into the genes within the living organisms through the evolutionary process over a long period of time. The genes are expressed by rhythms during the process of fetal development followed by growth. The environmental modifications ultimately are settled in genes, serving as a biological clock that is located putatively in the hypothalamus. Thus the biological clock governs a large number of rhythms and affects the time of birth and death lift expectancy, behavior, physiology, cell division, biochemical reaction, etc. The rhythms are readjusted to the changes of environmental cues. The biological clock has the great advantage of predicting and preparing the regular changes of environment.

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