Contact lens fitting requires some skills from an eye doctor. But lens insertion needs proper method from the wearers. Some contacts wearers may feel uncomfortable with their contact lenses. New wearers are more likely to incorrectly put on their lenses. A common situation is that a contact lens is inside out. The following are some ways to determine this problem and avoid it in the future.
One method is to look at the lens carefully from the inside. A contact lens on the tip of the index finger should be shaped like the letter "U", rather than a soup bowl. If it is flared on the sides like a soup bowl, it is surely inside out.
A second way to determine an inside out lens involves looking at it from the top. This method is especially useful for colored contact lenses. In general, the edge of a colored lens looks very blue. Inverted lenses look greenish, which require the wearer to flip it around for proper wearing.
Another effective way is to gently squeeze the lens so that the edges touch, which is named "taco test". The edges of a normal lens always touch completely after been squeezed. In contrast, the edges of a lens that is inside out will not touch fully.
Some contact lens manufacturers use special lasers to make factory engraving on their lenses. Common items of engraving include manufacturer information, model number, brand name and grade of materials used. This engraving will not affect normal vision of the wearer but it can be used to evaluate the right position of a lens on the eyes. Some brands of contacts engrave a label "1-2-3" on them. Wearers should make sure this label is facing downwards on the finger before placing the lens into the eye.
Contacts wearers can also visit a doctor if there is any discomfort of their contact lenses. Incorrectly placed contact lenses may still impose slight pressure on the eyes. New wearers of contacts always need much practice.
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