Dear higuy,
In the above history, you do not mention whether 20/400 is the best you can see with glasses or is your uncorrected acuity. This will be important in answering your question. Also, a visual field would help to determine the extent of damage from the episodes of retrobulbar neuritis.
Dr. Feldman
Sandy T. Feldman, M.D., M.S.
ClearView Eye and Laser Medical Center
San Diego, California
If the visual acuity you give (OU 20/400) is with best correction, than under the SSI/SSD criteria you are "legally" blind. However, that doesn't mean you can't work. Under the ADA employers are obligated to make reasonable accommodations to those with disabilities. If you are having problems seeing a computer screen, there are screen magnifiers and readers that you can use and request your employer to purchase for you. If you live in the U.S. try contacting your local commission/services for the blind office and also go and get a complete low vision evaluation from a competent optometrist or ophthalmologist who specializes in this area.