Exams {eye exam} can test for cataracts, glaucoma, and macular degeneration.
Axis
Axis is degrees at which to put cylindrical lens to give patient best vision. Axis is from 1 to 180 degrees.
Sphere
At Axis degrees, Sphere is diopters that give patient best vision. Plano or Pl {Plano} equals 0 diopters.
Cylinder
For Axis degrees plus or minus 90 degrees in the perpendicular direction, Cylinder is diopters that give patient best vision.
diopters
Sphere and Cylinder state lens strength in positive or negative diopters. Positive lenses enlarge, and negative lenses diminish. Lens strength is sum of Sphere diopters and Cylinder diopters. Higher positive is stronger. High-minus means lens is thicker at edge. High-plus means lens is thicker in middle.
Lens diopters add to eye diopters to result in total diopters. Nearsighted eyes have negative diopters, and glasses have positive diopters. Farsighted eyes have positive diopters, and glasses have negative diopters.
Prism and Base
Prism and Base can correct eye-muscle-problem altered eye orientations, but eye exams typically do not need to measure them.
Biological Sciences>Medicine>Medical Examination>Eye Exam
4-Medicine-Medical Examination-Eye Exam
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Date Modified: 2022.0224