Abstract: Polymer materials are useful as electrode array bodies for neural stimulation. They are particularly useful for retinal stimulation to create artificial vision, cochlear stimulation to create artificial hearing, and cortical stimulation, and many related purposes. The pressure applied against the retina, or other neural tissue, by an electrode array is critical. Too little pressure causes increased electrical resistance, along with electric field dispersion. Too much pressure may block blood flow. Common flexible circuit fabrication techniques generally require that a flexible circuit electrode array be made flat. Since neural tissue is almost never flat, a flat array will necessarily apply uneven pressure. Further, the edges of a flexible circuit polymer array may be sharp and cut the delicate neural tissue. By applying the right amount of heat to a completed array, a curve can be induced.

Abstract: Present invention is a method of improving circadian rhythms in blind people by stimulation the visual neural system. Ideally a retinal prosthesis of the type used to restore vision can be used to restore normal circadian rhythms. Additionally, brightness on the prosthesis can be increased in the morning and decreased in the evening to stimulate normal Circadian rhythms. Alternatively, if a retinal prosthesis is not preferable, the retina can be stimulated externally, during the day and not at night. While such eternal stimulation can not produced artificial vision, it can stimulate normal circadian rhythms.

Abstract: This invention is methods of reducing stress in the retina that are caused by the implanted electrode array body having an oval shape that is curved to conform to the curvature of the retina and having a mounting aperture in the body for attaching the electrode array to the retina with a tack where a strain relief internal tab is place around a strain relief slot.

Abstract: Electronic neural tissue stimulators for controlling the level of electrical stimulation in order to prevent damage to the neural tissue. Methods presented in the disclosure include detecting current leakage via electrode impedance measurement, electrode capacitance measurement, and testing the electrode response to a test current pulse. Apparatus presented in the disclosure include circuitry and systems capable of performing the methods disclosed.

Abstract: Directly modulating a beam of photons onto the retinas of patients who have vision impairment or blindness. Its purpose is to supply enough imaging energy to retinal prosthetics implanted in the eye which operate essentially by having light, activating photoreceptors, or photoelectrical material. Providing sufficient light amplification logarithmically. Output light level being at a safe level. Providing balanced biphasic stimulation with no net charge injection into the eye. Optical and electronic magnification is used for the image with an optical zoom lens. It would not be feasible to zoom in on items of particular interest or necessity. Without proper adjustment, improper threshold amplitudes would obtain, also uncomfortable maximum thresholds. Proper adjustment for the threshold amplitudes and maximum comfortable thresholds is provided.

Abstract: The invention is a retinal prosthesis with an inductive coil mounted to the side of the eye by means of a strap around the eye. This allows for close coupling to an external coil and movement of the entire implanted portion with movement of the eye ball.

Abstract: While a photolithographed array internal to the retina provides superior resolution, an array external to the retina provides easier implantation and improved manufacturability. Therefore it is advantageous to supply a high-resolution electrode array internal to the sclera, near the fovea and a lower-resolution electrode array eternal to the sclera near the periphery of the retina. Even if a separate lower-resolution array is implanted internal to the sclera, super-choroidal (between the choroid and sclera) or intra-scleral (between the layers of the sclera), it is easier to make a lower-resolution array in a curved shape.

Abstract: The invention is a process for cathodic protection of electrodes wherein negative bias is applied on the electrode. The negative bias is obtained by asymmetric current pulse, which is obtained by negative phase pulsing with higher amplitude than that of the anodic phase. The asymmetric current pulse is obtained by negative phase pulsing with wider pulse width than that of the anodic phase. The asymmetric current pulse may also be obtained by negative phase pulsing with both higher amplitude and wider pulse width than that of the anodic phase. The invention further relates to a process for cathodic protection of electrodes, wherein negative bias is applied on the electrode, and the negative bias is obtained by asymmetric current pulse, where the asymmetric current pulse is obtained by negative phase pulsing with wider pulse width than that of the anodic phase. The wider pulse width is obtained by pulse trains.

Abstract: A method and apparatus for improving visual acuity when providing a visual image from a “high” resolution input device to a “low” resolution output device. The described invention is of particular use when the output device is an array of electrodes as part of a retinal prosthesis used to restore vision to a visually-impaired patient. In that various limitations may, within the foreseeable future, limit the density of such an electrode array (and thus the resolution of the output image), the present invention teaches techniques to assign processed pixel subsets of a higher resolution image to a single electrode. By varying the pixel subsets, e.g., by jittering, and/or altering the processing criteria, the perceived visual acuity may be further improved. Alternatively and additionally, such processing may be further extended to drive neighboring electrodes in combination to thus stimulate virtual electrode sites and thus further enhance visual acuity.

Abstract: The present invention is an electrode array for neural stimulation. In particular it is an electrode array for use with a visual prosthesis with the electrode array suitable to be positioned on the retina. The array includes multiple attachment points to provide for even pressure across the electrode array surface. The attachment points are arranged so as to not damage retinal tissue stimulated by the electrode array.

Abstract: Polymer materials are useful as electrode array bodies for neural stimulation. They are particularly useful for retinal stimulation to create artificial vision, cochlear stimulation to create artificial hearing, or cortical stimulation many purposes. The pressure applied against the retina, or other neural tissue, by an electrode array is critical. Too little pressure causes increased electrical resistance, along with electric field dispersion. Too much pressure may block blood flow. Common flexible circuit fabrication techniques generally require that a flexible circuit electrode array be made flat. Since neural tissue is almost never flat, a flat array will necessarily apply uneven pressure. Further, the edges of a flexible circuit polymer array may be sharp and cut the delicate neural tissue. By applying the right amount of heat to a completed array, a curve can be induced.

Abstract: A method and apparatus for adjusting a visual image provided to a patient. In one embodiment, an image may be presented to the patient to obtain the patient's subjective perception of the image, and the patient may either manipulate the image to obtain a desired adjustment, or guide a clinician performing the adjustment. In another embodiment, the clinician may make objective observations of, for example, the position of an electrode array on the patient's retina, and make adjustments accordingly. The adjustment may be a spatial adjustment comprising a re-mapping performed to decreases image distortion resulting from differences in the patient's perception of stimulation of different areas of the retina. Such distortion may result from differences between the patient's perception of stimulation falling within the macula, and stimulation falling within the periphery surrounding the macula. The adjustment may also compensate for translations or rotations of the electrode array on the retina.

Abstract: Methods and devices for inductively coupled implants on the human or animal body are disclosed. An external coil assembly to be used with the implant has a transmitting coil and one or more receiving coils. The number of the receiving coils, their distance from the transmitting coil and their shape is chosen to reduce the influence of a noise signal received by the external coil assembly.

Abstract: A critical element of a retinal prosthesis is the stimulating electrode array, which is placed in close proximity to the retina. It is via this interface that a retinal prosthesis electrically stimulates nerve cells to produce the perception of light. The impedance load seen by the current driver consists of the tissue resistance and the complex electrode impedance. The results show that the tissue resistance of the retina is significantly greater than that of the vitreous humor in the eye. Circuit models of the electrode-retina interface are used to parameterize the different contributors to the overall impedance.

Abstract: A visual prosthesis apparatus and a method for limiting power consumption in a visual prosthesis apparatus. The visual prosthesis apparatus comprises a camera for capturing a video image, a video processing unit associated with the camera, the video processing unit configured to convert the video image to stimulation patterns, and a retinal stimulation system configured to stop stimulating neural tissue in a subject's eye based on the stimulation patterns when an error is detected in a forward telemetry received from the video processing unit.

Abstract: The present invention provides a flexible circuit electrode array adapted for neural stimulation, comprising: a polymer base layer; metal traces deposited on said polymer base layer, including electrodes suitable to stimulate neural tissue; a polymer top layer deposited on said polymer base layer and said metal traces at least one tack opening; wherein said polymer base layer, said metal traces and said polymer top layer are thermoformed in a three dimensional shape. The present invention provides further a method of making a flexible circuit electrode array comprising depositing a polymer base layer; depositing metal on said polymer base layer; patterning said metal to form metal traces; depositing a polymer top layer on said polymer base layer and said metal traces; preparing at least one tack opening; and heating said flexible circuit electrode array in a mold to form a three dimensional shape in said flexible circuit electrode array.

Abstract: A method and apparatus suitable for forming hermetic electrical feedthroughs in a ceramic sheet having a thickness of ?40 mils. More particularly, the method yields an apparatus including a hermetic electrical feedthrough which is both biocompatible and electrochemically stable and suitable for implantation in a patient's body. The method involves: (a) providing an unfired, ceramic sheet having a thickness of ?40 mils and preferably comprising ?99% aluminum oxide; (b) forming multiple blind holes in said sheet; (c) inserting solid wires, preferably of platinum, in said holes; (d) firing the assembly of sheet and wires to a temperature sufficient to sinter the sheet material but insufficient to melt the wires; and (e) removing sufficient material from the sheet lower surface so that the lower ends of said wires are flush with the finished sheet lower surface.

Abstract: A method and apparatus for adjusting a visual image provided to a patient. In one embodiment, an image may be presented to the patient to obtain the patient's subjective perception of the image, and the patient may either manipulate the image to obtain a desired adjustment, or guide a clinician performing the adjustment. In another embodiment, the clinician may make objective observations of, for example, the position of an electrode array on the patient's retina, and make adjustments accordingly. The adjustment may be a spatial adjustment comprising a re-mapping performed to decreases image distortion resulting from differences in the patient's perception of stimulation of different areas of the retina. Such distortion may result from differences between the patient's perception of stimulation falling within the macula, and stimulation falling within the periphery surrounding the macula. The adjustment may also compensate for translations or rotations of the electrode array on the retina.

Abstract: A visual prosthesis and a method of operating a visual prosthesis are disclosed. Neural stimulation through electrodes is controlled by spatial maps, where a grouped or random association is established between the pixels of the acquired image and the electrodes. In this way distortions from the foveal pit and wiring mistakes in the implant can be corrected. Moreover, broken electrodes can be bypassed and a resolution limit can be tested, together with testing the benefit the patient receives from correct spatial mapping.

Abstract: The present invention is a motion compensation system for a visual prosthesis to adapt a visual image to movement of a user's eyes and head. The system includes a camera providing a video signal, an eye movement tracking device, a head movement tracking device, and a video processing unit processing the video signal and correcting the video signal for eye and head movement. The corrected video signal is sent to an implanted neural stimulator including electrodes stimulating visual neurons to create a perception of the video image.