What does an observation of vertical corneal striae in the posterior central cornea suggest?

Vertical corneal striae observed in the posterior central cornea typically indicate the presence of excessive corneal edema. These striae are essentially folds or lines that develop in the corneal tissue due to swelling, which can occur when there is an accumulation of fluid in the cornea. This condition often arises when the cornea is subjected to stress, such as from an improper fit or prolonged wear of contact lenses, which can compromise the cornea's health and capacity to maintain its normal shape and hydration levels.

In the context of lens use, excessive corneal edema may arise from various factors, including poor oxygen transmission through the lens material, inadequate lens design, or inappropriate lens wear schedules. The presence of these striae signals that the cornea may be experiencing stress and is not receiving sufficient oxygen, necessitating immediate evaluation and possibly reconsideration of lens type or fit.