Standard Operating Procedures

Equipment: Clear Chart. Purpose: To determine the smallest letter/image a patient can discern at distance. Scope: Ophthalmic technicians, certified and uncertified. Testing Process: Check with correction unless doctor protocol states otherwise. (1) Position patient in exam chair. (2) Have the patient hold the occluder with the opening over the right eye first. (3) Ask the patient to read the chart. (4) Continue to reduce the size of the letter/pictures until the patient misses letters. (5) Record the smallest line that the patient can read more than half the letters correctly — include the number of letters missed (e.g. 20/20-1) or additional letters from the next line (e.g. 20/25+1). (6) Repeat for fellow eye. If acuity is 20/30 or worse, perform a pinhole acuity test: drop the pinhole over the affected eye, ask the patient to focus through one of the small holes, and record the smallest line they can read more than half of.