Step 8: Refraction at Near
Refracting at near (ie, determining the optimal correction, if any, needed for near vision) is not routinely done on patients younger than 40 years of age unless they have a specific near-vision complaint:
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Begin with the current distance correction in place in the phoropter or trial frame. If you do not know the distance refraction with confidence, perform a careful distance refraction even if the patient volunteered no complaints at distance.
Converge the phoropter, so that the optics point toward the near eye chart—use the 2 small levers just below the top of the instrument (Figure I-29). Install the near eye chart on the stick and holder provided for near work at a working distance of 40 cm (Figure I-30). (The multipanel “Rotochart” provided with the phoropter is excellent for near-vision testing. The “Rosenbaum card” also works well.) If this is not available, the patient can hold a near-vision testing card at the appropriate distance. Be sure to provide suitable illumination.
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Add plus sphere power over the distance correction until near acuity is optimized, with the zone of clear vision centered at 40 cm, or at the patient’s preferred reading distance. (Check this by sliding or moving the near card toward and away from the patient.)
Rough near-point “add” guidelines according to age are as follows: 40 years: +1.00 D to +2.00 D; 50 years: +1.50 D to +2.50 D; 60 years and older: +2.00 D to +2.75 D.
When in doubt, chose the lesser add. It should rarely be necessary to use an add greater than +2.75 D, except as a low-vision aid.
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.