What is the general shape of the normal human cornea?
Keratometry
No
U
A
The natural shape of the cornea is that it is steepest centrally and then gradually flattens toward the periphery. Another term for this is that the cornea is prolate. This natural prolate shape results in an apheric optical system and thus minimizes fluctuations in refractive error as the pupil changes size.
In contrast, an oblate cornea would be steeper peripherally than centrally. Such a cornea would increase spherical aberration and these individuals could have refractive error that fluctuates with pupil size.
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