Quote Originally Posted by bcipam
You guys know that the number say -13 or 5.50 reflects the curvature of your eye vs. the degree of nearsighted or farsightedness. What you really need to compare is eyeglass presciptions. For instance in my left eye I am 320/20 and right I am 275/20. My contact presciption is 5.50 for the left and 4.75 for my right. I don't think there is a correlation betwent he eye curvature and lack of vision but I may be wrong.
Not in my case. Contact lens power is expressed in units called diopters. Contact lenses that correct nearsightedness have a minus (-) lens power. Lenses that correct farsightedness have a plus (+) power. My power is actually -13.5.

My base curve is 8.6. That is the measurement of the radius of curvature in millimeters of the inside curve.