Contact Lenses

Contact lenses are thin, curved plastic shells that rest directly on the cornea of the eye and correct refractive errors. They offer an alternative to glasses and are worn by adults as well as, in certain situations, by children and adolescents.

How contact lenses work

The contact lens rests on the tear film of the cornea and, together with the eye, forms an optical system. Like a spectacle lens, it focuses the incoming light so that a sharp image forms on the retina. Because the lens sits directly on the eye, there are no frame restrictions and no fogging up during temperature changes.

Types of contact lenses

Soft contact lenses

Made of flexible, water-containing material
Comfortable to wear immediately
Available as daily, weekly, or monthly lenses
Correct nearsightedness, farsightedness, and corneal curvature
Multifocal versions are also available for age-related farsightedness

Rigid (hard) contact lenses

Made of gas-permeable, firmer material
Enable very good oxygen supply to the cornea
Particularly suitable for strong corneal curvature or keratoconus
Getting used to them takes a little longer than with soft lenses

Special lenses

Orthokeratology lenses (Ortho-K): rigid lenses that are worn overnight and temporarily reshape the cornea. During the day, no visual aid is then needed. They are also used for myopia control in children.
Scleral lenses: large rigid lenses that rest on the sclera (the white of the eye). They are helpful for certain corneal diseases.
Therapeutic contact lenses: used after injuries or operations to protect the cornea.

Contact lenses in children

Children can benefit from contact lenses in certain situations:

After cataract surgery: especially in infants who cannot yet receive an artificial lens
With high one-sided refractive error (anisometropia): contact lenses compensate for the difference in vision better than glasses
Myopia control: special contact lenses can slow the progression of nearsightedness in children
Sport and leisure: for athletically active adolescents, contact lenses offer more freedom of movement

Care and hygiene

Proper care is crucial to avoid complications:

Wash hands: wash your hands thoroughly with soap and dry them before every insertion and removal
Use cleaning solution: clean lenses only with the recommended solution, never with tap water
Replace the case regularly: replace the lens case at least every three months
Observe wearing times: do not wear lenses longer than recommended
Do not swim in water: remove contact lenses before swimming or wear tight-fitting swimming goggles
Do not sleep in them: except with lenses specifically approved for this

Possible complications

With improper use, problems can occur:

Corneal infections (microbial keratitis): potentially vision-threatening; presents with pain, redness, and deterioration of vision
Dry eyes: contact lenses can intensify the feeling of dryness
Allergic reactions: to the lens material or care products
Corneal neovascularization: ingrowth of blood vessels into the cornea due to chronic oxygen deficiency

When to see an ophthalmologist?

Remove the contact lenses immediately and seek medical help if:

Pain, redness, or light sensitivity occur
Vision suddenly deteriorates
There is persistent redness of the eye
A foreign-body sensation does not subside despite removing the lens

Regular eye check-ups, at least once a year, are important for all contact lens wearers in order to monitor the health of the cornea and adjust the visual correction.