Adapting to Contact Lenses

Today contact lenses are available in a rich variety and design. If used correctly they can provide perfect vision and comfort. Wearing contacts, however, has its risks particularly when they are not cleaned and changed regularly.
Contact lenses are made of different types of polymers. They can be divided into two main groups: soft and gas permeable lenses.
If you have decided to wear contact lenses have a precise eye examination, followed by adapting and training from an experienced ophthalmologist. In case you already wear contacts see an ophthalmologist once a year.
The assessment of soft contact lens fit is based on static and dynamic criteria. Static criteria are connected with the position and size of the lens as compared with that of the cornea. The edges of the lens should not be within the limbus, because it will cause discomfort and bad centration.
Dynamic criteria are connected with the spontaneous movement of the lens when the eye blinks.
Choice of the appropriate lens can be performed in the following way:

  1. Choice of the material
  2. Choice of the proper dioptre
  3. Choice of the lens radius
  4. Choice of the diameter of the lens

After the lens is put into the eye some observations are done on a biomicroscope. We look for the following characteristics:
Static:

  1. How is the lens centered?
  2. What part of the cornea does it cover?

Dynamic:

  1. Movement on blink in central gaze
  2. Movement in all main directions
  3. Movement on blink in up-gaze
  4. Push-up movement

In case these criteria are not observed, patients will suffer from headache, discomfort in close distance work.
Complaints about red eyes, blurred vision and recovery of vision on blinking are due to “tight lenses”. If lenses are “loose” patients complain of distorted vision and feeling of foreign body in the eye.