Yasushi Tsukahara

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The suppressive effect of sunglasses upon photoparoxysmal responses (PPRs) elicited by 15-Hz flicker stimuli with a low luminance of nearly 10 nits was studied in eight patients with photosensitive epilepsy. Using three commercially available sunglasses of neutral density (ND), blue, and brown, the influence upon generalized PPRs elicited by a flickering(More)
Using the visual stimulator, the effect of color on the photoconvulsive response (PCR) was studied in 14 photosensitive patients. When stimuli of 15 c/sec flickers of white, red, yellow, green and blue light of 20 cd/m2 were given to the subjects, generalized PCRs were provoked only by the red-flicker. These PCRs were all inhibited by blue light of 1.9(More)
On the evening of 16 December 1997 approximately 700 people around the nation (mostly children) were rushed to hospitals and treated for seizure symptoms. The youngsters had been watching the vastly popular TV animated cartoon series Pocket Monsters (Pokemon). We designated those individuals as a main group, who presumably had simultaneous occurrence of(More)
PURPOSE To determine whether tranilast administered to pigmented rats inhibits formation of choroidal neovascularization induced by diode-laser photocoagulation. METHODS Female Brown Norway rats were used. On day 0, choroidal neovascularization was induced by diode-laser photocoagulation, using a setting of 75 microm spot size, 0.1 second's duration, and(More)
OBJECTIVE We performed this study to elucidate the roles of stimulus spatial frequency and visual field in eliciting generalized photoparoxysmal response (PPR) by flickering dot pattern (FDP) stimulation. METHODS We studied 20 photosensitive epilepsy patients, aged 7-48 years (means +/- SD, 21.4+/-11.7 years), producing a 20 Hz FDP stimulation with a(More)
Overstimulation of the N-methyl D-aspartate (NMDA) receptor has been implicated as a factor in the pathogenesis of ischemic injury in the central nervous system. The present study was undertaken to determine whether ketamine hydrochloride, a potent NMDA antagonist, could attenuate ischemic injury in the rabbit retina. Retinal ischemia was induced for 60 min(More)
The fluorescein kinetics in the vitreous was simulated with a computer to consider several factors such as permeability of the blood-retinal barrier, outward active transport, plasma fluorescein dynamics, diffusion of fluorescein in the vitreous, and fluorescein leakage from the blood-aqueous barrier. Kinetic vitreous fluorophotometry was performed in(More)
The correlation between the effects of zopiclone (ZPC), a nonbenzodiazepine hypnotic drug, on sleep polysomnograms and on daytime EEGs was examined in 12 healthy adult male volunteers. Sleep polysomnograms were recorded after a single oral administration of ZPC 10 mg or placebo according to the double-blind crossover method. Daytime EEGs were recorded after(More)
Quantitative methods to measure ocular glucose consumption in vivo, which is dominated by the retina, could provide considerable information about retinal metabolism in healthy and disease states. Eyes that are totally ischemic for at least 4 hr retain good retinal histopathologic features if treated with vitreoperfusion. In such cases, the vitreoperfusion(More)
The effects of diazepam on the EEG were studied by means of EEG topographic mapping, using recordings with four different references. Subjects were ten healthy, right-handed, male volunteers aged 21-25 years. Double-blind crossover trials with a single oral dose of 10 mg diazepam and placebo controls were conducted in random sequence at intervals of one(More)