keratometric

Keratometric refers to the measurement of the curvature of the cornea, the transparent outer layer of the eye. This measurement is typically performed using an instrument called a keratometer, also known as an ophthalmometer. The keratometer projects a target onto the cornea and measures the reflections from its surface to determine its refractive power. This power is usually expressed in diopters and is measured along two principal meridians, representing the steepest and flattest curves of the cornea.

The keratometric readings are crucial in ophthalmology and optometry for several reasons. They are essential for fitting contact lenses, as the curvature of the lens must closely match that of the cornea for optimal comfort and vision. They also play a vital role in the planning and evaluation of refractive surgery, such as LASIK and PRK, where the goal is to reshape the cornea to correct vision problems like myopia, hyperopia, and astigmatism.

Furthermore, keratometry helps in diagnosing and monitoring corneal conditions like keratoconus, a progressive thinning and bulging of the cornea, which can significantly alter its curvature. Deviations from normal corneal curvature can also indicate the presence of astigmatism, a common refractive error where the eye does not focus light evenly onto the retina, leading to blurred or distorted vision at all distances. Accurate keratometric measurements are therefore fundamental to providing appropriate eye care and ensuring visual health.