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PubMed · 7135199

Vertical prisms. How to avoid them.

D D Michaels
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Abstract

Prescribing vertical prisms not infrequently leads to unsightly spectacles at best, and computing them may lead to errors at worst. Prismatic compensation for a particular reading point is of little value when the patient uses other eccentric portions of the lens, and it is not necessary if the patient learns to use (or continues to use) the optical centers. Clinical evaluation of eye-head posture and vertical phorias may reveal tell-tale clues in managing vertical imbalances in general and the anisometropic presbyope in particular.

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EyeglassesHumansPosturePresbyopiaJournal Article

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D D Michaels. Vertical prisms. How to avoid them.. https://doi.org/10.1016/0039-6257(82)90116-3

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