What action should be taken if there’s excessive vertex distance?

When there is excessive vertex distance, the appropriate action is to decrease the lens base curve. This adjustment helps bring the lenses closer to the eye, effectively reducing the vertex distance, which is the physical space between the back surface of the lens and the front surface of the eye. An increased vertex distance can lead to issues such as light refraction changes and may result in visual discomfort or poorer visual acuity, especially in high prescription lenses.

By reducing the base curve, the lens can be made flatter, which in turn minimizes the distance from the lenses to the eye. It not only enhances the optical performance of the glasses but also improves the overall fit and comfort for the wearer. It is crucial to consider this adjustment carefully, as altering the base curve can also affect other optical parameters, such as magnification and alignment. Overall, addressing excessive vertex distance by altering the lens base curve helps achieve optimal visual clarity and comfort for the patient.