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Papillary Conjunctivitis

Papillary Conjunctivitis is an allergic reaction of palpebral conjunctiva to the contact lens. Allergic reactions are more common amongst users of soft contact lenses. Conjunctival papillae then…

Peroxide system

The radical peroxide cleaning system is undoubtedly the most efficient and healthiest way to remove organic deposits from contact lenses. The principle consists of releasing reactive oxygen, which…

Photophobia

Photophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom, photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the…

PMMA

Polymethylmet­hacrylate – PMMA – is the oldest material that was used to produce hard contact lenses. This is the first use of plastic material in contactology. PMMA is…

Porosity of the material

Suitable porosity of the contact lens is important for the passage or the avoidance of substances. It is intended that both the chemical structure of the polymer partly received water. The…

Presbyopia

Presbyopia is the inability of the eye to focus at the normal reading distance – we are talking about the age of emerging farsightedness. It is a refractive defect, occurring usually after the…

Proteins

Sometimes, despite the excellent care of the soft contact lenses, they are susceptible to penetration of proteins, which can denature the antigen and treaten eyes. Together with an increased…

Pseudomonas

The most common pathogen met in the contact lenses for extended wear, is the he bacterium Pseudomonas aeruginosa. It may cause damage to the cornea. After removing the…

Ptosis

In connection with contact lenses, we can often see eye slits narrowing due to the decline of the upper eyelid, known as ptosis. Ptosis occurs due to disfunction of the muscles that raise…