• Journal of Biomedical Engineering Research
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• v.24 no.2
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• pp.91-97
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• 2003

The Propose of this paper is hierarchical detection method for the optic disc in fundus image. We detected the optic disc boundary by using the Prior information. It is based on the anatomical knowledge of fundus which are the vessel information. the image complexity. and etc. The whole method can be divided into three stages . First, we selected the region of interest(ROI) which included optic disc region. This is used to calculate location and size of the optic disc which are prior knowledge to simplify image preprocessing. And then. we divided the fundus image into numberous regions with watershed algorithm and detected intial boundary of the optic disc by reducing the number of the separated regions in ROI. Finally, we have searching the defective parts of boundary as a result of serious vessel interference in order to detect the accurate boundary of optic disc and we have removing and interpolating them.

• The Journal of the Korea Contents Association
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• v.5 no.6
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• pp.138-145
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• 2005

This paper describes a technique for detecting the boundary of the optic disk in digital image of the retina using inward and outward curve evolution. This paper offers medical information about glaucoma progresses. For accurate boundary detection, image inpainting based on texture synthesis removes blood vessels crossing the optic disk. For removing noises and preserving boundary of optic disk in image inpainting process, the anisotropic diffusion filtering is necessary. After pre-processing, the optic disk boundary is determined using inward and outward curve evolution. The experimental results show that the algorithm is effective for detection of optic disk boundary.

• Journal of the Korean Society of Radiology
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• v.11 no.5
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• pp.313-319
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• 2017

The purpose of this study is to confirm the double of optic foramen in Korean and apply it to the Rhese method. First, the angle between the right optic foramen and the MSP was measured on the axial image using MPR technique of the 3D CT. Second, we measured the angle between the right optic foramen and OML in sagittal of MPR images. As a result, the angle between the optic foramen and the MSP was $39.9{\pm}4.63^{\circ}$ on average, which was different from the $53^{\circ}$ presented by Rhese method(p<0.05). The angle between optic foramen and OML was $40.8{\pm}6.6^{\circ}$. In conclusion, this study confirms that the standard of the Rhese method proposed in current textbook is difficult to apply to Koreans. Therefore, it is necessary to study angle of Korean standard in various general x-ray technique.

• Progress in Medical Physics
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• v.18 no.1
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• pp.42-47
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• 2007

Purpose: To evaluate the tracing of optic nerve tract using manganese enhanced magnetic resonance Imaging. Materials and Methods: After injecting $30{\mu}l$ of $MnCl_2(1mol)$ (1 mol) Into the retina of female New Zealand white rabbit, the contrast enhancements at major anatomical structures of optic nerve tract were evaluated by high resolution T1-weighted Images 12 hours, 24 hours, and 48 hours after $MnCl_2(1mol)$ Injection using 3D FSPGR (Fast Speiled Gradient Recalled echo) pulse sequence at 1.5T clinical MR scanner with high performance gradient system. Also, for quantitative evaluation, the signal-to-noise ratios of circular ROI on anatomical locations were measured. Results: The major structures on the optic nerve tract were enhanced after injecting $MnCl_2(1mol)$. The structures, which showed enhancement, were right optic nerve, optic chiasm, left optic tract, left lateral geniculate nucleus, left superior colliculus. The structures on the contralateral optic pathway to the right retina were enhanced whereas the structures on the ipsilateral pathway did not show enhancement. Conclusion: The Mn transport through axonal pathway of optic nerve sys)em was non- invasively observed after injecting injecting $MnCl_2$ at the retina, which is the end terminal of optic nerve system. This Mn transport seems to occur by voltage gated calcium $(Ca^{2+})$ channel and In case of direct Injection Into the retina, the fast transpori pathway of voltage gated calcium channel seems to be responsible for Mn transport.

• Journal of The Korean Ophthalmological Society
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• v.59 no.11
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• pp.1091-1096
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• 2018

Purpose: We report a case of bilateral nonarteritic anterior ischemic optic neuropathy (NAION) following acute angle-closure crisis (AACC). Case summary: A 76-year-old female visited our clinic because of a 1-day history of ocular pain and vision loss in both eyes. The visual acuity was 0.02 in both eyes and her intraocular pressure (IOP) was 52 mmHg in the right eye (RE) and 50 mmHg in the left eye (LE). She had corneal edema and a shallow anterior chamber in both eyes, with 4 mm fixed dilated pupils. After decreasing the IOP with intravenous mannitol, laser iridotomy was performed. However, 2 days later, visual acuity was further reduced to finger counting at 10 cm RE and at 50 cm LE, and her optic disc was swollen. Bilateral NAION following AACC was diagnosed. One month later, visual acuity slightly improved to 0.02 RE and 0.04 LE, and the optic disc edema resolved. A small cup-disc ratio, optic disc pallor, and atrophy were observed. Humphrey visual fields demonstrated superior and inferior altitudial visual field defects in the LE, and almost total scotoma in the RE. Conclusions: AACC can be a predisposing factor for NAION, so the relative afferent pupillary defect, papilledema, and presentation of other risk factors are important clues to a diagnosis of NAION.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.4
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• pp.249-254
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• 2007

This paper describes a technique for detecting the boundary of the optic disk in digital image of the retina using inward and outward curve evolution. Optic disk boundary offers medical information about glaucoma progresses. For accurate boundary detection, image inpainting based on PDE removes blood vessels crossing the optic disk. For removing noises and preserving boundary of optic disk in image inpainting process, the anisotropic diffusion filtering is developed. After pre-processing, the optic disk boundary is determined using inward and outward curve evolution. Experimental results show that blurring effect of original region and optic disk boundary is reduced considerably. By the proposed method, we can detect correct disk boundary compare to conventional method.

• Proceedings of the Zoological Society Korea Conference
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• 1998.10b
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• pp.73-73
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• 1998

No Abstract, See Full Text

• Journal of The Korean Radiological Technologist Association
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• v.29 no.1
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• pp.249-249
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• 2003

• Neonatal Medicine
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• v.16 no.1
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• pp.81-84
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• 2009

Septo-optic dysplasia is a rare congenital disorder characterized by the absence of the septum pallucidum, hypoplasia of the optic chiasma and nerves, and various types of hypothalamic-pituitary dysfunction. Schizencephaly is an abnormal cleft in the brain, lined with gray matter which may communicate with the ventricular system. Septo-optic dysplasia with schizencephaly is associated with endocrinologic disorders, visual impairment, mental retardation, and seizures. We report a case of septo-optic dysplasia with schizencephaly which was diagnosed in the early neonatal period.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.3
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• pp.324-331
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• 1991

Ocular injuries often accompany midfacial trauma Blindness related to indirect optic nerve injury in midfacial fractures is an uncommon and usually permanent complication. Opic nerve blindness is secondary to an indirect optic nerve injury due to the skeletal distortion that occurs in a facial fracture and almost all are caused by frontal, nasoethmoido-frontal or Le Fort III type fractures. When the loss of vision following midfacial fractures is complete and immediate, the prognosis is poor in spite of treatment. Computed tomography revealed compressin of the optic nerve by bony fragments. And so if injury to the optic nerve is suspected, a CT-scan must be performed and massive steroid therapy must be started as soon as possible. Surgery must be performed if there are hematoma or bony fragments injuring the nerve. The following report concerns two patients who suffered immediate and total loss of vision due to a midfacial fracture with no improvement after massive steroid therapy and surgial decompression.