What does a keratometer specifically measure?

A keratometer specifically measures the curvature of the cornea. This instrument is crucial for assessing the shape of the cornea, which plays a significant role in how light is focused onto the retina. By determining the curvature, optometrists can gather essential information for fitting contact lenses, diagnosing conditions such as astigmatism, and planning corneal surgeries. The readings obtained help in understanding the optical characteristics of the eye, thereby aiding in personalized patient care.

In contrast, measuring the pressure inside the eye pertains to tonometry, which is used to assess intraocular pressure for conditions like glaucoma. The thickness of the cornea is assessed using pachymetry, while the diameter of the pupil is measured using a pupillometer. Each of these measurements serves a distinct purpose in eye care, but the keratometer's focus on the corneal curvature is fundamental for optimal lens fitting and visual clarity.