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A novel in vitro sensing configuration for retinal physiology analysis of a sub-retinal prosthesis.

Koo KI, Lee S, Yee JH, Ryu SB, Kim KH, Goo YS, Cho DI - Sensors (Basel) (2012)

Bottom Line: This paper presents a novel sensing configuration for retinal physiology analysis, using two microelectrode arrays (MEAs).Results show that the geometrical relation between the stimulation microelectrode locations and the response locations seems very low.These results provide useful guidelines for developing a sub-retinal prosthesis.

View Article: PubMed Central - PubMed

Affiliation: Inter-university Semiconductor Research Center, Automation System Research Institute, School of Electrical Engineering and Computer Science, Seoul National University, Seoul 151-744, Korea. kkin76@snu.ac.kr

ABSTRACT
This paper presents a novel sensing configuration for retinal physiology analysis, using two microelectrode arrays (MEAs). In order to investigate an optimized stimulation protocol for a sub-retinal prosthesis, retinal photoreceptor cells are stimulated, and the response of retinal ganglion cells is recorded in an in vitro environment. For photoreceptor cell stimulation, a polyimide-substrate MEA is developed, using the microelectromechanical systems (MEMS) technology. For ganglion cell response recording, a conventional glass-substrate MEA is utilized. This new sensing configuration is used to record the response of retinal ganglion cells with respect to three different stimulation methods (monopolar, bipolar, and dual-monopolar stimulation methods). Results show that the geometrical relation between the stimulation microelectrode locations and the response locations seems very low. The threshold charges of the bipolar stimulation and the monopolar stimulation are in the range of 10~20 nC. The threshold charge of the dual-monopolar stimulation is not obvious. These results provide useful guidelines for developing a sub-retinal prosthesis.

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Related in: MedlinePlus

The graph of average number of the evoked RGC spikes. (a) Average number of the evoked RGC spikes of the 1–6, 4–3, 5–3, and 7–1 electrodes in both monopolar and bipolar stimulations. (b) Average number of the evoked RGC spikes of the 7–1 microelectrodes in all cases.
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f8-sensors-12-03131: The graph of average number of the evoked RGC spikes. (a) Average number of the evoked RGC spikes of the 1–6, 4–3, 5–3, and 7–1 electrodes in both monopolar and bipolar stimulations. (b) Average number of the evoked RGC spikes of the 7–1 microelectrodes in all cases.

Mentions: Results insofar described the data from one patch, however, monopolar and bipolar stimulations were performed for three patches. Ensuing discussions include all 3 set of data. Figure 8(a) show the average number of the evoked RGC spikes of the 1–6, 4–3, 5–3, and 7–1 microelectrodes, which get excited in monopolar and bipolar stimulations. Figure 8(b) show the average number of the evoked RGC spikes of the 7–1 microelectrode, which gets excited in all monopolar, bipolar, and dual-monopolar stimulations. According to Figure 8, the threshold charges of the monopolar and bipolar stimulations are located in the range of 10∼20 nC (which corresponds to 10∼20 μA × 1 ms). However, the threshold charge of the dual-monopolar stimulation method is not clear in the data obtained.


A novel in vitro sensing configuration for retinal physiology analysis of a sub-retinal prosthesis.

Koo KI, Lee S, Yee JH, Ryu SB, Kim KH, Goo YS, Cho DI - Sensors (Basel) (2012)

The graph of average number of the evoked RGC spikes. (a) Average number of the evoked RGC spikes of the 1–6, 4–3, 5–3, and 7–1 electrodes in both monopolar and bipolar stimulations. (b) Average number of the evoked RGC spikes of the 7–1 microelectrodes in all cases.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3376591&req=5

f8-sensors-12-03131: The graph of average number of the evoked RGC spikes. (a) Average number of the evoked RGC spikes of the 1–6, 4–3, 5–3, and 7–1 electrodes in both monopolar and bipolar stimulations. (b) Average number of the evoked RGC spikes of the 7–1 microelectrodes in all cases.
Mentions: Results insofar described the data from one patch, however, monopolar and bipolar stimulations were performed for three patches. Ensuing discussions include all 3 set of data. Figure 8(a) show the average number of the evoked RGC spikes of the 1–6, 4–3, 5–3, and 7–1 microelectrodes, which get excited in monopolar and bipolar stimulations. Figure 8(b) show the average number of the evoked RGC spikes of the 7–1 microelectrode, which gets excited in all monopolar, bipolar, and dual-monopolar stimulations. According to Figure 8, the threshold charges of the monopolar and bipolar stimulations are located in the range of 10∼20 nC (which corresponds to 10∼20 μA × 1 ms). However, the threshold charge of the dual-monopolar stimulation method is not clear in the data obtained.

Bottom Line: This paper presents a novel sensing configuration for retinal physiology analysis, using two microelectrode arrays (MEAs).Results show that the geometrical relation between the stimulation microelectrode locations and the response locations seems very low.These results provide useful guidelines for developing a sub-retinal prosthesis.

View Article: PubMed Central - PubMed

Affiliation: Inter-university Semiconductor Research Center, Automation System Research Institute, School of Electrical Engineering and Computer Science, Seoul National University, Seoul 151-744, Korea. kkin76@snu.ac.kr

ABSTRACT
This paper presents a novel sensing configuration for retinal physiology analysis, using two microelectrode arrays (MEAs). In order to investigate an optimized stimulation protocol for a sub-retinal prosthesis, retinal photoreceptor cells are stimulated, and the response of retinal ganglion cells is recorded in an in vitro environment. For photoreceptor cell stimulation, a polyimide-substrate MEA is developed, using the microelectromechanical systems (MEMS) technology. For ganglion cell response recording, a conventional glass-substrate MEA is utilized. This new sensing configuration is used to record the response of retinal ganglion cells with respect to three different stimulation methods (monopolar, bipolar, and dual-monopolar stimulation methods). Results show that the geometrical relation between the stimulation microelectrode locations and the response locations seems very low. The threshold charges of the bipolar stimulation and the monopolar stimulation are in the range of 10~20 nC. The threshold charge of the dual-monopolar stimulation is not obvious. These results provide useful guidelines for developing a sub-retinal prosthesis.

Show MeSH
Related in: MedlinePlus