Una rThe glasses box contains a series of values that indicate to the ophthalmologist the visual characteristics of the patient and, therefore, how their lenses should be.
En Área Oftalmológica Avanzada We explain how to read a prescription for glasses.
How to read or interpret a prescription for glasses?
To know how to read a prescription for glasses, it is necessary to know the values that may appear in it:
Dial
It refers to the diopters or power that the lens needs to correct the myopia o farsightedness:
- If the values are negative (-), it means that there is myopia.
- When the values are positive (+), it is farsighted.
Cylinder
Shows how many diopters are needed to correct the astigmatism in patients with two different graduations in the eye, due to a cornea not spherical.
This value can be positive or negative, depending on whether there is hyperopic or myopic astigmatism.
Addition
It is the magnification power that is added to the multifocal lenses, in their lower part, to correct the presbyopia. This is an always positive value, even if the (+) symbol does not appear in front of it, and it is always the same for both eyes.
Visual acuity
La visual acuity refers to normal vision values, that is, the quality that vision should have according to statistics.
It can be reflected in two ways:
- With percentages (100%, 50%, etc.).
- Through decimals (1.0, 1.2, etc.).
Normal vision is one that reaches a value of 100% or 1.0.
Complementary values in the graduation recipe
The following are values that can also appear in a glasses prescription, so it is important to know them for a complete interpretation of it:
prism and base
El prism is associated with squint, so it will only appear in the prescriptions of patients with a deviated eye, or both. It is measured through prismatic diopters, and reflects the level of deviation of the eye.
The base indicates the direction of the deviation, and how the prism should be oriented in the lens (top, bottom, outer, or inner).
Interpupillary distance
It is the distance between the pupils, expressed in millimeters. It has no clinical value, but it is useful to find the center of the lenses when mounting the glasses.
Meaning of abbreviations
The abbreviations that can be found in a glasses prescription and their meanings are as follows:
- LE: left eye
- OD: right eye
- AO: both eyes
- ESF: sphere
- CYL: cylinder
- ADD: addition
- AV: visual acuity
- VP: near vision
- VL: far vision
- VI: intermediate vision
Is a prescription for glasses the same as a prescription for contact lenses?
No, a prescription for glasses is not the same as a prescription for contact lenses, since the latter requires information that does not appear in the glasses prescription, and that can only be obtained through a contact lens consultation and adaptation.
Example of a glasses prescription
A prescription for myopia with astigmatism could be expressed like this:
OD: +3,75 (-1,25 x 180 °) RO: +3,75 (-0,75 x 175 °)
And also in this way:
DO: (180 ° x -1,25) +3,75 LE: (175 ° x -0,75) +3,75
En Área Oftalmológica Avanzada We can help you if you have any questions about your glasses prescription. Get in touch with us, we will be happy to assist you!
