2008 MacFarland Seminar, July 22, 2008
Training and Rehabilitation with Visual Prosthetics
The miracle of restoring partial sight to the blind is moving from dream to possibility in our times. Restoration of functional vision through the use of implanted retinal prosthetic devices that provide a neurotrophic effect to stimulate nerve growth factors in the retina in patients with photoreceptor degeneration continues to evolve. For those who have no remaining functional vision, the day is approaching when a retinal prosthetic will provide functional vision for everyday tasks by detecting the light with a camera and stimulating the retina with an implanted chip. Any successful implant must be biocompatible and display long-term durability. One day, it may be possible to regenerate essential retinal elements that may eventually repair retinal damage. It is hoped that a combination of basic science research and prosthetic device development may one day restore functional vision in patients who are legally blind.
Visual prosthetics R&D programs to date have focused on overcoming the technical challenges such as: 1) biocompatibility; 2) electrical interface for signal transmission; and 3) to make a larger array of “photoreceptor pixels” while still having a prostheses that is accepted by the retina / eye. With the promise of new biotechnologies, it is important not to lose sight of the fact that these novel clinical care and research strategies must ultimately be shown to benefit the person. These strategies require, therefore, the development of validated outcomes measures instruments that have been fully tested and designed to evaluate the essential everyday functional abilities of patients with visual impairments as well as people who have profound vision loss. These instruments should be used to acquire evidence that these new technologies and other innovative rehabilitative interventions improve activities of daily living and quality of life. Until recently there has been very little consideration for determining the functional vision efficacy of a prostheses.
There is a need to accurately and effectively measure not only the pre-implantation everyday function compared to the post-implantation everyday function but also any resultant improvement in independence and quality of life.
As part of a wider effort to discuss these issues among the various stakeholders (rehabilitation professionals, consumers, caregivers, and manufacturers/companies) the MacFarland Seminar will stimulate a dialogue among the diverse professionals providing rehabilitation for people who would be candidates for a visual prostheses or other biotechnology therapy (e.g., gene therapy or stem cell therapy). Topics that will be discussed include: proper controls to determine efficacy of the interventions, visual function efficacy testing methodologies, evaluation of functional vision performance including evaluation of self-report PRO instruments. Issues to be discussed include:
- Does pre-blindness visual experience impact on adaptation to the prosthesis?
- For what aspects of everyday life tasks does the implantation of a prostheses give better function in everyday life activities than training alone?
- What rehabilitative training contributes to optimal benefit of the prostheses?
- When should rehabilitative training be started; before or after the retinal prosthesis implantation?
- Should the retinal prosthesis be custom developed/made for each person based on their personal goals?
Topics and speakers include*:
Ron Schuchard, Seminar Leader
Overview of the current state of the art in Retinal Prosthetics: Gislin Dagnelie, Johns Hopkins University
The Potential of Prosthetics to Improve O&M Activities:
Duane Geruschat, Johns Hopkins University
The Perspective from the Manufacturer's/Company's Point of View: Matt MacMahon, Second Sight Medical Products, Inc.
New Bio Technologies on the Horizon but Soon to be in Clinical Trials: Ronald Schuchard, Atlanta VA Rehabilitation R&D Center of Excellence
*Schedule and speakers are subject to change