How to Read Toric Contact Lens Prescription

Toric contact lens prescriptions are usually used to correct distance vision and astigmatism and contain a series of numbers that indicate your individual vision correction and the type and size of contacts you need. Understanding these numbers can be confusing but once you know the basics, you can figure out how to read what your toric contact lens prescription means.

Instructions

• 1

  Obtain a written copy of your contact lens prescription. Your eye doctor is required by law to give you a copy of your contact prescription once he has verified the fit of the lenses.

• 2

  Locate the prescription strength. This is written as power or PWR. You may notice that the power of your contacts is different from your glasses and this is a normal variation, due to vertex distance or where your lenses sit in front of your eyes.

• 3

  Notice the cylinder and axis, or CYL and AXIS. All toric lenses will have a cylinder correction, which is the strength needed to correct your astigmatism. The numbers are written in .25 steps and are usually anywhere from .25 to 4.00 but can go higher. Axis is the location of the astigmatism and can be anywhere from 0 to 180.

• 4

  Locate Base Curve (B.C.) and Diameter. These numbers indicate the size of your lenses. Base curves are used to match the curves of your eye and diameter is the size of your contact from edge to edge in millimeters.

• 5

  Locate the brand of contact. Most doctors will prescribe a specific manufacturer or contact lens company that designs a lens to fit your individual needs. There are many different lens manufacturers but most doctors work with a limited number of companies.

• 6

  Observe other items on the prescription, which can include color for tinted contacts or ADD, which is a bifocal power in a multifocal contact lens. Not all toric contact prescriptions will contain these additional specifications.