What does the appearance of transient bubbles near the periphery of a contact lens indicate?

The appearance of transient bubbles near the periphery of a contact lens is indicative of flat posterior peripheral curves. These bubbles form when there is insufficient clearance between the lens and the cornea, often due to the curvature of the lens being too flat in the peripheral areas. When the curves are too flat, they can fail to adequately conform to the shape of the eye, resulting in trapped air or moisture that manifests as bubbles. This can lead to discomfort and may affect the lens's movement and overall fit, which is why it's essential to monitor these bubbles during fitting.

Other options do not effectively explain the phenomenon: a steep base curve might actually improve lens fitting and reduce bubble formation by conforming better to the shape of the eye; a large optical zone could influence vision but doesn't directly correlate with bubble formation; and narrow posterior peripheral curves would likely create a deeper fit, again minimizing the chance of bubbles appearing. Therefore, the presence of these transient bubbles is specifically linked to having flatter peripheral curves rather than the characteristics outlined in the other choices.