Massachusetts Institute of Technology

Massachusetts Eye and Ear Infirmary

John L Wyatt, Jr

Joseph F Rizzo, Iii

David J Edell

Hae-Seung Harry Lee

Luke Theogarajan

Steve Decker

Joseph F Rizzo

An ocular device that can more safely and effectively perform all functions needed of a retinal prosthesis with electronic components that are placed outside the wall of an eye, are powered wirelessly provided by an external power source, and which provide a patient with a view determined by natural motion of the eye and triggered by natural incident light converging at the retina. In one aspect, the invention is an externally powered, light-activated, sub-retinal prosthesis in which natural light entering the eye conveys visual details to the sub-retinal prosthesis, while wireless radiofrequency transmission provides the power needed to stimulate the retina, which would be insufficient if it were obtained from the intensity of incoming light alone.

Minimally invasive retinal prosthesis

Dynamically functional intra-ocular prosthesis. The prosthesis includes an implantable intra-ocular lens and microelectronic components mounted on the lens. One embodiment is a variable focal length implantable intra-ocular lens system for adjusting the focal length of the implantable lens. In one embodiment, a micromotor changes the tension in a band encircling the peripheral portion of the deformable lens changing its shape to vary its focal length. Another embodiment is an artificial intra-ocular lens which serves as a holding substrate for microelectronic components that form part of a prosthesis to stimulate the neural elements of the eye to restore vision to patients who are blind from retinal disease.

Intra-ocular lens system including microelectric components

A low-pressure neural contact structure for contact with neural tissue, for example, neural tissue of the retina within which are ganglion cells to be electrically stimulated. The contact structure comprises a first portion for attachment to a first bodily location, such as the inner surface of the retina, and a second portion interconnected with the first portion via an interconnection and being held in contact with the neural tissue. The interconnection exhibits a weak restoring force which in conjunction with the geometry of said second portion provides a preselected desired pressure of contact against the neural tissue. As adapted for the retina, the interconnection exhibits a weak restoring force developed in response to curvature of the interconnection along the inner radius of the retina.

Low-pressure neural contact structure

Low pressure neural contact structure

The invention provides a method for preferentially stimulating neural somas over neural axons located around the somas but not integral with the somas. In the invention, a positive electrical pulse is applied to a region of neural tissue consisting of one or more neural somas to be stimulated and neural axons, and due to the physiology of the somas, they are preferentially stimulated by the electrical pulse over the neural axons not integral with the somas to be stimulated. The preferential soma stimulation provided by the invention achieves the advantage of locally focusing external stimulation such that it may be directed to particular soma locations for indicating location-dependent sensory information. Thus the pulse scheme of the invention may be employed in prosthetic applications directed to, for example, the retinal ganglia neural tissue.

Method and apparatus for preferential neuron stimulation

A simple transistor circuit which acts as a linear resistor for small applied voltages, but becomes extremely resistive for large applied voltages is disclosed. Two-dimensional resistive grids comprising these resistive fuses can be employed to smooth and segment discretized images in machine vision. Existing and previously proposed VLSI implementations of resistive fuses have required at least thirty-three transistors. The resistive fuse circuit of the present invention uses only four transistors in its simplest embodiment, thus making it possible to design much denser vision arrays.

Growing community of inventors

Sudbury, MA, United States of America

John L Wyatt, Jr