A Tissue Change After Suprachoroidal-Transretinal Stimulation with High Electrical Current in Rabbits

Purpose: To investigate the safety range of current by suprachoroidal-transretinal stimulation (STS) using a high-current continuous stimulation. Method: Sclerotomy was performed at the area just beneath the visual streak of rabbits and the platinum (Pt) electrode (diameter: 100μm or 200μm) embedded in silicone plate was attached on the fenestrated sclera. Return electrode was placed in the vitreous cavity. Retina was stimulated by biphasic pulses (anodic first, duration: 0.5,msec, frequency: 20,Hz) with a current ranged from 1 to 3,mA continuously for an hour. The rabbit eyes were enucleated immediately after microscopic fundus observation, fixated with glutar-aldehide, embedded in paraffin and stained with hematoxylin-eosin.

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