Purchase this article with an account.
A. Messias, H. Zhang, A. Stett, A. Möller, A. Schatz, S. Julien, U. Schraermeyer, K. U. Bartz-Schmidt, E. Zrenner, F. Gekeler; A Fully Implantable, Freely Programmable Micro-Stimulator for Chronic Electrical Stimulation in Small Animals. Invest. Ophthalmol. Vis. Sci. 2009;50(13):4576.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To test functionality and biocompatibility of a newly developed, completely implantable, pre-programmable and battery-operated electric pulse generator for chronic electric stimulation in small animals.
18 female Sprague Dawley rats (80 - 100g) underwent surgery. After complete encapsulation, the units weighed 2.4 g, measured 4 x 16 x 20 mm and were pre-programmed to generate biphasic current pulses (1 ms; 20 Hz; 100 µA) for 30 minutes, four times a day. Retinal function, assessed with electroretinography (ERG), and measurements of stimulus amplitudes were performed weekly for three weeks. After this period, the device was explanted, the silicon protection film was examined, and histological evaluation of the retinas was performed.
14 rats completed 3 weeks follow-up. We detected 3 ruptured sub-conjuntival electrodes 1 week after surgery, while in the other 11 animals, stimuli pulse could be measured at the cornea until the third week follow-up. In these 11 eyes, pulse amplitude was 14.5 ± 11.2 mV with variations of 21 ± 12 % over time. There was no signal of ocular or retinal damage (histology), and electroretinographic responses showed no alterations on rods or cone pathways in any of these healthy animals. Silicon film and electrodes showed minor erosion and there were no signs of intense inflammatory reaction in the subcutaneous space.
We present a newly developed device for ocular electric stimulation, implantable in small (80 g) animals. The system is biocompatible and functions for at least 3 weeks. This device can also have application in other areas of neuroscience requiring controlled and safe electrical stimulation of neural tissue over extended periods, such as deep-brain, cochlea, thalamus, and in evaluating safety and efficacy of neural prostheses.
This PDF is available to Subscribers Only