What does a prescription with SPH=plano, CYL=-0.25, and AXIS=90 on both eyes mean?

It means your glasses are as close to plain window glass as it is possible to be. If these glasses were prescribed for protection from strong light (tinted) or if this was part of a progressive glasses Rx (with a bifocal section at the bottom for reading), this might make sense. If they were prescribed to improve your visual acuity and nothing more, it is possible the optician just needed to make a sale.

_Written by J. Trevor Woodhams, M.D. - Chief of Surgery, Woodhams Eye Clinic