Which corneal condition is explicitly listed as a good candidate for spherical GP lenses?

• A. WTR corneal astigmatism
• B. ATR corneal astigmatism
• C. Irregular astigmatism
• D. No corneal astigmatism

Answer: (A)

A spherical GP lens is most effective when the corneal astigmatism is regular and mild, especially with-the-rule. In with-the-rule astigmatism, the vertical meridian is steeper, and a spherical front surface paired with the tear layer can neutralize part of the corneal cylinder, giving clearer, more stable vision without needing a toric lens design. Against-the-rule astigmatism and irregular astigmatism present more complex surface curvatures that a simple spherical GP cannot adequately neutralize, so those situations typically require toric GP lenses or specialized designs. If there is no corneal astigmatism, a spherical GP is also a solid choice, but the option listed as a good candidate here reflects the regular, mild astigmatism scenario that spherical GP lenses handle well.