Re: Ueno et al.: Corneal thickness profile and posterior corneal astigmatism in normal corneas (Ophthalmology 2015;122:1072-8)

We read with interest the article by Ueno et al1 on corneal thickness and astigmatism. The authors stated, “It was found that the cornea was thicker in the vertical than in the horizontal direction, which can explain why the posterior cornea surface tends to be more [against-the-rule] astigmatic than the anterior corneal surface, as demonstrated by recent studies.” Clarification would be helpful. A steeper posterior corneal meridian aligned vertically correlates with the finding that the cornea is thicker along the vertical meridian.