What is the primary purpose of performing keratometry?

The primary purpose of performing keratometry is to measure corneal curvature. This measurement is essential for various reasons, particularly in the fitting of contact lenses and in planning for surgical procedures such as cataract surgery or refractive surgery.

The curvature of the cornea plays a crucial role in how light is focused onto the retina, and variations in this curvature can significantly influence a person's vision. By obtaining accurate measurements of the corneal surface, eye care practitioners can determine the appropriate curvature needed for lenses and evaluate the overall health of the cornea as well.

In the context of the other options, measuring intraocular pressure is a separate procedure typically done with tonometry, assessing visual acuity involves different tests to gauge how well a person can see, and examining the retina requires different techniques such as ophthalmoscopy or fundus photography. Each of these serves distinct purposes in the field of ophthalmology, emphasizing that keratometry specifically targets the curvature of the cornea.