What kind of astigmatism is described as having greater power in the vertical meridian than in the horizontal meridian?

The type of astigmatism characterized by having greater optical power in the vertical meridian compared to the horizontal meridian is known as with-the-rule astigmatism. In this condition, the cornea or lens is shaped such that it has more curvature in the vertical direction, causing light to focus more sharply along the vertical axis than along the horizontal.

This distinction is important in optometry and ophthalmology as it affects how a person's vision is corrected. With-the-rule astigmatism generally indicates that the individual may require a cylindrical lens that has more prescription power in the vertical meridian to achieve clear vision.

Understanding the differences between various types of astigmatism, including how the curvature of the cornea differs across meridians, is crucial for anyone learning about vision and eye care.