If you want to increase tear exchange in a lens fitting, what must be done?

Increasing tear exchange in a lens fitting is crucial for maintaining ocular health and comfort, particularly for patients who might experience dryness or discomfort while wearing contact lenses. When the optical zone of the lens is increased, it allows for greater movement of the lens over the corneal surface. This movement facilitates the pumping action that occurs with each blink, enabling more tears to flow beneath the lens.

A looser fit provides a reservoir that can enhance the exchange of tears, allowing for better hydration of the cornea and removal of debris or stagnated tears. Achieving this requires a careful adjustment of the lens fit, specifically through an increase in the optical zone, which can result in enhanced tear film stability and overall comfort.

In contrast, making the fit tighter or keeping the optical zone the same would likely hinder the movement and tear exchange capability, leading to less effective tear replenishment beneath the lens. Switching to daily disposable lenses might offer benefits in terms of hygiene and convenience, but it would not systematically increase tear exchange in the same manner as adjusting the optical zone. Therefore, the correct method to enhance tear exchange is loosening the fit by increasing the optical zone.