Which corneal curvature category corresponds to fitting with a larger GP lens?

• A. Steeper than 45D
• B. Flatter than 41D
• C. Normal cornea
• D. Irregular cornea

Answer: (B)

In GP lens fitting, the corneal curvature guides the lens’ base curve and overall size. A flatter cornea has a larger radius of curvature, which lowers the diopter value. To fit such a cornea well, you typically choose a flatter base curve lens and often a larger overall diameter to maintain good alignment, centration, and tear exchange. Flattening the lens surface to match the cornea’s gentler curve helps avoid excessive central clearance and edge issues, producing a stable, comfortable fit.

So, a cornea flatter than 41 diopters best corresponds to using a larger GP lens. Steeper than 45D would need a tighter, steeper fit (smaller radius), normal cornea is a standard range that doesn’t imply the need for a larger lens, and irregular cornea refers to conditions that often require specialty designs rather than simply a larger lens.