Title:
網膜補綴物
Document Type and Number:
Japanese Patent JP3929701
Kind Code:
B2
Abstract:
A method of focused phosphene generation through deeper intermediate retinal cellular electrical stimulation to the exclusion of direct ganglion cellular electrical stimulation comprises the steps of: a) positioning a stimulating electrode in the vicinity of retinal tissue; and b) applying a long duration stimulation signal to the electrode such that deeper intermediate retinal cells are preferentially stimulated over the retinal ganglion cells and proximal overlying surface axons. The long duration stimulation signal is preferably a biphasic signal having a negative and a positive phase pulse which is applied in cathodic fashion. To preferentially stimulate the deeper intermediate retinal elements the duration of the long duration stimulation signal is greater than 0.5 millisecond per phase pulse, and preferably equal to or longer than 2 millisecond per phase pulse. The biphasic signal is preferably adjusted to simulate a monophasic signal by adjusting the magnitude of the negative pulse in relation to positive pulse, and by adjusting the duration of the positive pulse in relation to the negative pulse to maintain approximately net zero charge introduction. Preferably, the ratio of the negative pulse to the positive pulse is approximately 10:1 or greater.
Inventors:
Greenberg, Robert, Jay.
Humayun, Mark, S.
Dujan, Eugene, Juniors
Humayun, Mark, S.
Dujan, Eugene, Juniors
Application Number:
JP2000535412A
Publication Date:
June 13, 2007
Filing Date:
March 11, 1999
Export Citation:
Assignee:
Johns Hopkins University
International Classes:
A61F9/007; A61F9/08; A61N1/36
Domestic Patent References:
| JP8511697A |
Foreign References:
| US5109844 | ||||
| US5397350 | ||||
| US4551149 | ||||
| US5109844 |
Attorney, Agent or Firm:
Yuichi Yamada
Yoshiki Hasegawa
Yoshiki Hasegawa