If an RGP is fitted too tightly, which adjustment is recommended?

When a rigid gas permeable (RGP) lens is fitted too tightly, modifying the diameter by 1mm is a recommended adjustment to alleviate the tightness. A lens that is too snug may restrict proper movement and may lead to discomfort for the wearer. Increasing the diameter allows for more edge lift, which can improve lubrication under the lens and enhance overall comfort.

While altering the base curve or changing the lens power can also be options for adjustments depending on specific fitting issues, they generally address different concerns. For example, changing the power alters vision correction without necessarily addressing the fit. Similarly, altering the base curve primarily affects how the lens conforms to the cornea's shape, but if the lens is overly tight in diameter, adjusting the diameter directly targets the fitting issue. Switching to a softer material might provide a different feel but does not immediately solve the fit issue of a lens that is currently too tight.