1.Normal Oscillatory Potentials in Rabbits.
Journal of the Korean Ophthalmological Society 1995;36(3):457-465
Ten pigmented raqbits were dark adapted for 30 minutes previously and then exposed to room illumination of 200 lux for 10 seconds. In mesopic adaptation, the oscillatory potentials(OPs) were recorded. The coefficient of variation in the peak latency, time interval, summed amplitude, and amplitude of each individual OP wavelet were obtained. The peak latency showed the smallest coefficient of variation. The summed amplitude of the OPa and the time interval showed smaller coefficient of variation than amplitude of each individual OP component. Therefore the peak latency, summed amplitude, and time interval may be reliable factors to evaluate the OPs. The increase of the light stimulus did not affect the amplitude of O3. However, O1 and O2 tended to increase in amplitude and O4 to decrease as the intensity of light stimulus increased. These facts may suggest that each individual component of OP has different orign. As the intensity of light stimulus increased, the summed amplitude of OPs was increased and peak latency of O1, O2, O3, and O4 were decreased. Time intervals showed no significant changes.
Lighting
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Rabbits*
2.Optimization of Exposure Condition and Photographic Techniques for Specimen and Devices in Neuroangiographic Suites.
Soonchan PARK ; Ok Kyun LIM ; Jin Ho YOUN ; Tae il KIM ; Seon Moon HWANG ; Han Soo KIM ; Jaegeun SHIM ; Eun Hye KIM ; Yun Gyeong JEONG ; Ha Young LEE ; Bohyun KIM ; Deok Hee LEE ; Dae Chul SUH
Neurointervention 2010;5(2):91-96
PURPOSE: We analyzed factors related to quality of photographs taken at neuroangiographic suites to optimize exposure condition. MATERIALS AND METHODS: We used a camera (EOS-300D, Canon Inc., Tokyo) with a standard- (EF-S 18-55 mm F3.5-5.6 USM, Canon Inc., Tokyo) and a macro-lens (EF 100 mm f/2.8 Macro USM, Canon Inc., Tokyo). Photographs were taken at a light-booth (1000 lux) and 2 neuroangiographic suites (988 and 856 lux) under ordinary intensity of illumination. We took photographs of a test chart (ColorChecker, X-rite, Michigan) and Kodak Q-13 Grey Scale Card at different values of aperture and shutter speed with fixed ISO of 400 and assessed the quality of photographs by Blade Pro (V1.1, Image group, Seoul). We analyzed photographs of a device at 1/25-1/80 shutter speed and F12 - 20 apertures and compared the result and also made visual assessment. RESULTS: Photographs of test chart and Grey Scale Card revealed that the best images chosen by Blade Pro were distributed in scattered range of quality which could help understand the range of optimum exposure condition but was not suitable for practical usage. We obtained reasonable quality photograph at shutter speed of 1/40 and aperture of F16 that can be used in 3 places. CONCLUSION: The most appropriate exposure condition when taking photographs in neuroangiographic suites could be explored. To get an optimal image in limited illumination, it is mandatory to select a fast enough shutter speed to avoid motion artifacts and a sufficient aperture to actualize the subject depth.
Artifacts
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Lighting
3.Effect of Illunmination on Stereoacuity.
Chang Hwan LEE ; Dong Gyu CHOI
Journal of the Korean Ophthalmological Society 2002;43(10):1963-1967
PURPOSE: To investigate the effect of illumination on stereoacuity and to evaluate adequate illumination for each stereotest. METHODS: We measured stereoacuity by Titmus stereotest, TNO stereotest, Lang stereotest in normal group of 40 cases and strabismus group of 26 cases with five levels of illumination. The statistical analysis was performed to compare the mean stereoacuity between different levels of illumination using Student t-test. RESULT: In Titmus stereotest, stereoacuity improved as illumination increased up to 60 lux, which was statistically significant (P< 0.05). In TNO stereotest, stereoacuity significantly improved as illumination increased up to 200 lux in normal group (P< 0.01), and up to 60 lux in strabismus group (P=0.01). In Lang stereotest, 100% of normal group passed the test under 20 lux or more, and 100% of strabismus group passed the test under 60 lux or more. DISCUSSION: The illumination of 60 lux or more was required for Titmus stereotest and 200 lux or more for TNO stereotest, which was sufficient with the room illumination. Lang stereotest is less influenced by illumination and could be performed under lower illumination than other stereotests.
Humans
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Lighting
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Strabismus
4.Effect of Illumination on Contrast Sensitivity.
Journal of the Korean Ophthalmological Society 1987;28(4):729-732
The effect of illumination on the contrast sensitivity function was studied using an Arden Contrast Sensitivity System and incandescent electric lamp. The intensities of illumination were set at 50,100,200,500, and 1,000 lx. The contrast sensitivity function was saturated at 500 lx of illumination in both monocular and biocular condition. But frequency charicteristics showed that the CSF was increased more at 1,000 lx of illumination at high frequency.
Contrast Sensitivity*
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Lighting*
5.Photopic Negative Response (PhNR) in Normal Subjects.
Hoon Dong KIM ; Sang Hyouk PARK ; Su Eun PARK ; Young Hoon OHN
Journal of the Korean Ophthalmological Society 2009;50(10):1531-1538
PURPOSE: To evaluate the nature of photopic negative response (PhNR) in normal subjects. METHODS: The electroretinogram (ERG) waves were recorded in 52 eyes of 26 normal subjects with UTAS E-3000(R) (LKC Technologies Inc., Gaithersberg, MD, USA). Photopic cone response was obtained for analysis from a white flash with white background illumination (group 1) and a red flash with blue background illumination (group 2), after stimulations ranging from 0.007674 cd.s/m2 (-25dB) to 7.736 cd.s/m2 (5dB) with a 5dB interval. RESULTS: PhNRs were observed in all 52 eyes in group 1 stimulated with the white flash at 0.9933 cd.s/m2 (-4dB). PhNRs were also observed in all 52 eyes in group 2 at 2.4297 cd.s/m2 (0dB) after stimulation with the red flash. There was correlation between the amplitudes of PhNR and intensity of stimuli (p<0.001). Implicit times of PhNR were correlated with age in both groups, but amplitudes decreased with age in group 1. CONCLUSIONS: The amplitudes of PhNR were correlated with intensity of stimuli and age had an influence on PhNR. Standardization of examination conditions is necessary when recording PhNR.
Eye
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Humans
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Lighting
6.Enhanced Peripheral Retinal Illumination by Curved Endoilluminator During Phakic Vitrectomy.
Journal of the Korean Ophthalmological Society 1998;39(1):139-144
Illumination and access of instruments to peripheral fundus are limited by lens in phakic vitrectomy. The purpose of this study was to determine if curved endoilluminator could enhance visibility of peripheral fundus in phakic virectomy. Ten consecutive cases of pars plana vitrectomy were done for vitreous opacity. Indirect laser photocoagluation was done to make four reference points of distance from optic disc to nasal ora serrata. We evaluated the respective extent of nasal peripheral view with the use of curved or straight endoilluminator which was inserted through temporal scleral port. When compared with the straight endoilluminator, the curved endoilluminator enhanced the visualization of peripheral fundus(p<0.05). A curved endoilluminator may be a useful surgical adjunct during the phakic vitrectomy and other advantages and disadvantages of its use are discussed.
Lighting*
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Retinaldehyde*
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Vitrectomy*
7.Critical Fusion Frequency in Normal Eyes.
Journal of the Korean Ophthalmological Society 1972;13(4):231-237
C.F.F. in 14 normal eyes with normal visual acuity was examined at central, 5 degrees and 10 degrees to the nasal and temporal portion in the horizontal meridians with rotating sectored disc(light dark ratio=1:1). The distance between the target and the subject was 50cm. 1. C.F.F. was higher in the mydriatic state than in the miotic state, examined with the suround illumination of 50 lux. 2. C.F.F. was higher with 2cm target than with 1cm target, examined with the surround illumination of 50 lux in the mydriatic state. 3. C.F.F.was higher in the light adapted state than in the dark adapted state, examined in the mydriatic state. 4. The more the examined field located peripherally, the higher the C.F.F.
Lighting
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Meridians
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Visual Acuity
8.Success Rate of Endonasal Dacryocystorhinostomy Based on the Location of the Lacrimal Sac.
Eui Ryun CHUNG ; Kyung Taek LEE ; Woong Chul CHOI
Journal of the Korean Ophthalmological Society 2002;43(10):2000-2004
PURPOSE: We studied whether the illumination had an influence on the identification of the location of the lacrimal sac and the success rate of endoscopic endonasal dacryocystorhinostomy (DCR). METHODS: Endoscopic endonasal DCR was performed on 85 eyes of 80 patients who had obstruction of nasolacrimal system without illumination. RESULTS: In all patients, identification of the location of the lacrimal sac by detecting the probe tip or the lacrimo-maxillary suture line was accomplished, without illumination. Final success rate was 87.1% in illuminator non-using group. CONCLUSIONS: We considered that endoscopic endonasal DCR without illumination, in the knowledge of lacrimal sac, ethmoid anatomy, and anatomical variations, was a non-invasive, efficient, and satisfactory method.
Dacryocystorhinostomy*
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Humans
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Lighting
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Sutures
9.Development of slit-lamp microscope and its applications in optics.
Chinese Journal of Medical Instrumentation 2013;37(6):437-440
This paper mainly introduces the origin and development of the slit-lamp microscope, the basic structure, working principle and test methods, focuses on diffuse illumination, direct focal illumination, indirect illumination, retro illumination, zone of specular reflection and slit-lamp filter used in the optical inspection, to provide the reference for clinical general optometry practitioners and using slit-lamp microscope widely and standardized.
Lighting
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instrumentation
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Ophthalmology
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instrumentation
10.Transscleral LED illumination pen.
Christian LINGENFELDER ; Frank KOCH ; Philipp KOELBL ; Pia KLANTE ; Martin HESSLING
Biomedical Engineering Letters 2017;7(4):311-315
Existing light sources for intraocular illumination are often bulky and expensive and pose a risk for the patient, because light guides are inserted in the eye through incisions and if the tip of these light guides get too close to the retina, the retina can be damaged photochemically within minutes or even seconds. Therefore a new, safe and simple device for intraocular illumination is developed and evaluated for its thermal and photochemical risks to the patient. It consists of a white LED which is integrated into a pen like holder. This device is pressed against the sclera by the physician who seeks for illumination during surgery or for diagnostic purposes. The LED light is transmitted through the sclera without the need for an incision. Considering the relevant standards, the device poses no harm to the patient, and in tests with the authors' own eyes a sufficient intraocular illumination is reached. The proposed device is quite simple but easy to handle and very gentle for the patient.
Humans
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Lighting*
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Retina
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Sclera