|Intraorbital optic nerve stimulation with penetrating electrodes: in vivo electrophysiology study in rabbits|
|Li, Liming1; Cao, Pengjia1; Sun, Mingjie1; Chai, Xinyu1; Wu, Kaijie1; Xu, Xun2; Li, Xiaoxin3; Ren, Qiushi1|
|关键词||Visual prosthesis Optic nerve Electrophysiology Penetrating electrodes EEPs (electrically evoked potentials) VEPs (visually evoked potentials)|
|刊名||GRAEFES ARCHIVE FOR CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY|
|WOS标题词||Science & Technology|
|关键词[WOS]||SUBRETINAL ELECTRICAL-STIMULATION ; RETINAL PROSTHESIS ; MORPHOMETRIC-ANALYSIS ; VISUAL PROSTHESIS ; RETINITIS-PIGMENTOSA ; SCIATIC-NERVE ; DEGENERATED PHOTORECEPTORS ; MACULAR DEGENERATION ; GANGLION-CELLS ; INNER RETINA|
To investigate the response properties of the electrically evoked potentials (EEPs) elicited by intraorbital optic nerve stimulation with penetrating electrodes using different stimulus parameters.
Visually evoked potentials (VEPs) were recorded as a control and for comparative purposes. Teflon-coated tungsten wire electrodes (100 mu m core-diameter, 300 mu m exposed tip) were inserted intraorbitally into the optic nerve. A charge-balanced biphasic current was delivered to the optic nerve via inserted wire electrodes in 26 anaesthetized rabbits. EEPs were recorded by epidural electrodes placed over the visual cortex. The charge density threshold for eliciting EEPs was determined. Stimulus pulse amplitude, duration, frequency and waveform were varied to study their effects on EEPs. After the experiments, the stimulated optic nerves were examined histologically for examination of implantation position of the stimulating electrode into the optic nerve tissue.
EEPs were successfully elicited by intraorbital optic nerve stimulation with penetrating electrodes. The measured amplitude of the first large positive peak (P1) was smaller and the latency of P1 was shorter compared with VEPs. The measured charge density threshold to elicit EEPs was 21.36 +/- 5.64 mu C/cm(2). The amplitude of P1 increased and the latency of P1 decreased with increasing pulse amplitude of fixed duration stimuli. The amplitude of P1 increased with increasing pulse duration of fixed amplitude stimuli. For fixed charge stimuli, the amplitude of P1 decreased and the latency of P1 increased as the pulse duration increased. As frequency of stimuli varied from 1 to 10 Hz, the amplitude of P1 decreased monotonically. Among the different charge-balanced biphasic pulse stimulating waveforms, the symmetrical cathode-first biphasic pulse elicited the largest amplitude of P1.
Our study demonstrates that intraorbital optic nerve stimulation with different stimulus parameters by penetrating electrodes can evoke cortical responses with different properties. The short-duration symmetrical cathode-first biphasic pulses of current with low frequencies are more efficacious in eliciting electrophysiological responses in the visual cortex than other stimulating waveforms.
|项目编号||2005CB724302 ; 60588101 ; 07pj14050 ; 05DZ22318 ; 05DZ22325 ; 04DZ05114|
|资助机构||National Basic Research Program of China ; National Science Fund for Distinguished Young Scholars from The National Natural Science Foundation of China ; Shanghai Pujiang Program ; Shanghai Commission of Science and Technology|
|作者单位||1.Shanghai Jiao Tong Univ, Dept Biomed Engn, Inst Laser Med & Biophoton, Shanghai 200240, Peoples R China|
2.Shanghai Jiao Tong Univ, Dept Ophthalmol, Affiliated Shanghai Peoples Hosp 1, Shanghai 200080, Peoples R China
3.Beijing Univ, Dept Ophthalmol, Affiliated Beijing Peoples Hosp, Beijing 100044, Peoples R China
|Li, Liming,Cao, Pengjia,Sun, Mingjie,et al. Intraorbital optic nerve stimulation with penetrating electrodes: in vivo electrophysiology study in rabbits[J]. GRAEFES ARCHIVE FOR CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY,2009,247(3):349-361.|
|APA||Li, Liming.,Cao, Pengjia.,Sun, Mingjie.,Chai, Xinyu.,Wu, Kaijie.,...&Ren, Qiushi.(2009).Intraorbital optic nerve stimulation with penetrating electrodes: in vivo electrophysiology study in rabbits.GRAEFES ARCHIVE FOR CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY,247(3),349-361.|
|MLA||Li, Liming,et al."Intraorbital optic nerve stimulation with penetrating electrodes: in vivo electrophysiology study in rabbits".GRAEFES ARCHIVE FOR CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY 247.3(2009):349-361.|