The Radiuscope is primarily used to measure which parameter for contact lens fittings?

The Radiuscope is primarily used to measure which parameter for contact lens fittings?

• A. Sag
• B. Base curve of RGP
• C. Base curve of soft lens
• D. Peripheral curves of RGP

Answer: (B)

Radiusscope is used to measure the back surface curvature of a contact lens—the base curve. This parameter is the key to how a rigid gas-permeable lens sits on the cornea, influencing centering, movement, and tear film distribution. Getting the base curve right ensures the lens aligns well with the eye and provides predictable wear. Soft lenses don’t rely on this same back-surface radius measurement, and the Radiusscope isn’t used to assess peripheral curves. It’s specifically focused on the posterior radius of curvature, i.e., the base curve of rigid lenses.

Radiusscope is used to measure the back surface curvature of a contact lens—the base curve. This parameter is the key to how a rigid gas-permeable lens sits on the cornea, influencing centering, movement, and tear film distribution. Getting the base curve right ensures the lens aligns well with the eye and provides predictable wear. Soft lenses don’t rely on this same back-surface radius measurement, and the Radiusscope isn’t used to assess peripheral curves. It’s specifically focused on the posterior radius of curvature, i.e., the base curve of rigid lenses.