Classification of Keratoconus

Keratoconus has been classified in a number of ways. One method is by the keratometer readings as follows:

Classification

Mild

Moderate

Advanced

Severe

Keratometer Readings

<45.00D

45.00 to 52.00D

52.00 to 62.00D

>62.00D

The unit "D" is diopters, or units of corneal power.

Another method (or in combination with the above) is to use the morphological shape:

Round or Nipple

Oval or Sagging (pictured at left)

Ill-defined

With the availability of corneal topographers a more quantitative description is possible and results in a more accurate description where the actual position of the cone (axis and distance) from the visual axis can be given as well as the dioptric power at the peak of the cone.