Spherical equivalent and transposition
Summarizes spherocylindrical refraction in one value (spherical equivalent), transposes the cylinder and classifies myopia using International Myopia Institute criteria.
Calculate with transparency
Check the population, units and version. The result shows the formula or classification; it does not make an automatic treatment decision.
Preparing the form…
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Method · Limits of application
Thibos 1997: power M, J0, J45; spherocylindrical transposition axis ±90°
Thibos’s 1997 representation describes the power of thin spherocylindrical lenses through vector components. It does not by itself establish a clinical classification of myopia or standardize refractive-examination conditions. The IMI classification and refraction technique must match their respective sources.
Conditions of use
Check the population, units, inclusion and exclusion criteria, and version in the original source. A result alone does not establish a diagnosis, discharge decision or prescription.
Documented parameters
- Sphere · D
- Cylinder · D
- Cylinder axis · degrees
4/4 reference cases checked. Numerical tests are not clinical validation.
Relationship with cancer research
General context — relationship to be defined
A resource for general clinical contexts. This edition does not assign a specific oncological relationship; selecting it for a study requires a justified question, population and purpose.