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Tear duct

The tear duct is the eye’s drainage system for tears. The valve serves to open or close the duct, allowing passage of tears.

Tear film

Tears produce corneal tear film, which generally has a thickness from 0.005 to 0.012 mm and is renewed every 10 to 30 seconds. Its function is to keep the cornea smooth and shiny, protecting…

Tear secretion

Tear secretion is glandular activity, consisting of a secretion of substances that are necessary for the function of the eye. Basal tear secretion – resting constant tear…

Tearing

Tearing , lacrimation, or lachrymation, is the secretion of tears, which often serves to clean and lubricate the eyes in response to an irritation of the eyes. Tears formed through crying are…

Temple Arm Length

The temple arm length is measured from the beginning to the end including the bend at the end of the arm. Most common temple arm length falls between 120 mm and 150 mm. Supposing our…

Therapeutic contact lens

Therapeutic (curative) contact lenses are used to reduce sharp light, moisturizing the cornea when it is damaged, as a bandage after eye surgery, as a drug carrier, allergies to the patch, in the…

Toxic reaction

In contact with a contact lens, some pharmacological agents or preservatives accumulate and cause a toxic reaction (for example the formation of the

Transferrin

This is a blood glycoprotein whose function is to generate the emergency supply of blood and to transport it to the mechanism of endocytosis into cells. It is situated in the liquid…

Transmisibility

Transmissibility means the oxygen permeability of a particular contact lenses. Indicates the material's ability to transmit gas to the central membrane thickness. This quantity is called…

Transparency of the cornea

This is the transparency of the cornea. Normal visual acuity is determined by the transparency of optical media. The endothelium of…

Trauma

This is generally a mechanical irritation of eye tissues (cornea, conjunctiva, eyelid), which may result in a inflammation of the eye…

Trichiasis

Trichiasis is a condition where the initially correct eyelashes turn against the eyeball. It irritates the cornea and conjunctiva – see trauma. The most…

Тhermal decontamination

This is the safest way to clean contact lenses – from the emergence of possible allergic reactions to care for contact lenses. It is an outdated…