 In glasses with powers beyond ±4.00D, the vertex distance can affect the effective power of the glasses.A shorter vertex distance can expand the field of view, but if the vertex distance is too small, the eyelashes will come into contact with the back of the lens, smudging the lens and causing annoyance for the wearer.A skilled frame stylist will help the wearer select a good balance of fashionable frame size with good vertex distance in order to achieve ideal aesthetics and field of view.