The sagittal value of any contact lens is a key factor to truly fit contact lenses.
These images depicts a very steep irregular corneo-scleral shape with a low sagittal value lens (Flat) which promoted the formation of folds as the lens landed flat onto a steep surface (high sag). After modifying parameters (base curve radius, peripheral curve radius and diameter) the sagittal value increased to match the shape of the corneo-scleral profile. The result: a well centered lens which aligned its optical center with the visual axis and a tangential resting onto the conjunctiva.
Manufacturers should provide the sag value and the eccentricity of their contact lenses and contribute to scientifically fit contact lenses instead of fitting by trial and error (guess work).
We should stop selecting lenses by the wrong association between the base curve and the keratometry readings.
Any thoughts about soft lens sag values, eccentricity, corneo-scleral shape and fitting soft contact lenses?