Hyperopia

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Far-sightedness (also called hyperopia and hypermetropia) is when an object at infinity would be focused behind the retina without accommodation. It is corrected with Plus lenses, yay. Hyperopia is the opposite of myopia, many of the EM techniques work for hyperopia, but your blur horizons and the signs on everything are backwards. Remember that all the pages written about myopia are using negative numbers, and myopes need to practice distance AF, while hyperopes need to practice near AF.

A myope's prescription will be for the distant/far side of their visual range. Normalized/distance lenses will be very close to the prescription, and differentials/close lenses will be for near vision. A hyperope's prescription is for near side of their visual range, so the near lenses should be close to prescription, and the far lenses are the ones that need adjusting.

Keep your signs straight on your math! You need more plus or less minus for close vision, less plus or more minus for distance vision.

Components

Total hyperopia: total amount of hyperopia which is obtained after complete relaxation of accommodation using cycloplegics like atropine, equal to the sum of all of these:

  • Latent hyperopia: corrected by ciliary tone (approximately 1 diopter), requires cycloplegics to detect
  • Manifest hyperopia: not corrected by ciliary tone
    • Facultative hyperopia: corrected by accommodation
    • Absolute hyperopia: residual part of hyperopia that blurs distance vision

Young people tend to be hyperopic with no absolute hyperopia and become emmetropic from axial elongation.

References