What typically triggers the onset of VLK?

The onset of contact lens-related conditions such as VLK, or "vortex lens keratitis," is often associated with low edge lift of the lens. Low edge lift can lead to inadequate tear exchange and proper lens positioning on the cornea. When the lens does not turn properly in the tear film, it can create a stagnant environment underneath the lens, which may result in corneal irritation or damage.

Proper edge lift is important as it facilitates fluid exchange, allowing tears to flow beneath the lens and keeping the corneal surface hydrated and free of debris. If the edge lift is too low, the lens may sit too closely against the cornea, resulting in less movement and limited ability for the tears to nourish the cornea effectively. This lack of movement can contribute to the development of VLK, where inflammation and keratitis become more likely due to the accumulation of irritants and reduced oxygen transmission to the corneal epithelium.

Understanding the dynamics of edge lift and its implications on corneal health is crucial for effective contact lens fitting and maintaining the health of the ocular surface.