Why should a soft lens never be fit with apical clearance?

Fitting a soft contact lens with apical clearance is not advisable because it can lead to a tight fit. In the context of soft lenses, an optimal fit should allow for some movement of the lens over the cornea in order to maintain a level of comfort and promote healthy tear exchange beneath the lens. If a lens is fitted with apical clearance, it creates excessive space at the center of the lens which does not allow for this necessary movement, resulting in a poor fit that can lead to discomfort and inadequate tear exchange.

Additionally, a tight fit can compromise the lens's ability to remain appropriately centered on the cornea. This stability is crucial for both comfort and effective vision correction. A lens that is too tight may also induce corneal distortion or contribute to other complications, which emphasizes the importance of striving for a proper fitting with the right balance of alignment and movement of the lens relative to the eye.