In a case of high astigmatism fitted with a spherical RGP, where will the lens typically show touch?

In cases of high astigmatism, when a spherical rigid gas permeable (RGP) lens is fitted, it often leads to a situation where the lens will show touch horizontally on the surface. This occurs because the shape of the cornea—typically toric in astigmatism—introduces variations in the curvature that the spherical lens cannot adequately match.

As the lens rests on a cornea with varying slopes, the areas of greatest curvature (the meridians) may not align with the spherical base curve of the lens. This mismatch can result in the lens touching more in the horizontal meridian, where it aligns better with the flatter corneal profile, leading to touch across that area. Therefore, the horizontal touch is indicative of the lens's adaptation to the underlying corneal contours.

The other options would not typically manifest in this scenario due to the nature of astigmatism and the design of the spherical RGP lens, which is generally not optimized for the cylindrical shapes that would be present in a high astigmatism condition.