9.1. a. The Social Security website states, “We consider you to be legally blind under Social Security rules if your vision cannot be corrected to better than 20/200 in your better eye, or if your visual field is 20 degrees or less, even with a corrective lens.”
9.2. a. The rule of thumb for adding prism to high-add spectacles over 4.00 D is to incorporate base-in prism for each eye at a correction that is 2 D greater than the required add power.
9.3. b. The American Academy of Ophthalmology’s Preferred Practice Pattern regarding vision rehabilitation recommends that patients with acuity less than 20/40, contrast sensitivity loss, peripheral field loss, or central field loss be referred for low vision evaluation.
Excerpted from BCSC 2020-2021 series : Section 3 - Clinical Optics. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.