What does central pooling in RGPs indicate?

Central pooling in rigid gas permeable (RGP) lenses indicates that the lens is too steep and too tight on the cornea. When a lens does not have proper alignment with the eye's surface, the tear film beneath the lens cannot be distributed evenly. This leads to pooling of tears in the central area of the lens, which is a sign that the lens curvature is not appropriate for the corneal shape.

In this particular case, the steeper fit means that the base curve of the lens is too curved relative to the cornea, leading to a lack of adequate movement and causing the tear film to gather in the center of the lens. Proper fitting is essential for comfort and vision, and recognizing central pooling is crucial for practitioners to adjust the lens fit accordingly. Thus, understanding central pooling helps in ensuring that RGP lenses provide optimal vision and comfort for the wearer.